perlapi - autogenerated documentation for the perl public API
This file contains most of the documentation of the perl public API, as generated byembed.pl. Specifically, it is a listing of functions, macros, flags, and variables that may be used by extension writers. Besidesperlintern andconfig.h, some items are listed here as being actually documented in another pod.
At the end is a list of functions which have yet to be documented. Patches welcome! The interfaces of these are subject to change without notice.
Some of the functions documented here are consolidated so that a single entry serves for multiple functions which all do basically the same thing, but have some slight differences. For example, one form might process magic, while another doesn't. The name of each variation is listed at the top of the single entry. But if all have the same signature (arguments and return type) except for their names, only the usage for the base form is shown. If any one of the forms has a different signature (such as returningconst or not) every function's signature is explicitly displayed.
Anything not listed here or in the other mentioned pods is not part of the public API, and should not be used by extension writers at all. For these reasons, blindly using functions listed inproto.h is to be avoided when writing extensions.
In Perl, unlike C, a string of characters may generally contain embeddedNUL characters. Sometimes in the documentation a Perl string is referred to as a "buffer" to distinguish it from a C string, but sometimes they are both just referred to as strings.
Note that all Perl API global variables must be referenced with thePL_ prefix. Again, those not listed here are not to be used by extension writers, and may be changed or removed without notice; same with macros. Some macros are provided for compatibility with the older, unadorned names, but this support may be disabled in a future release.
Perl was originally written to handle US-ASCII only (that is characters whose ordinal numbers are in the range 0 - 127). And documentation and comments may still use the term ASCII, when sometimes in fact the entire range from 0 - 255 is meant.
The non-ASCII characters below 256 can have various meanings, depending on various things. (See, most notably,perllocale.) But usually the whole range can be referred to as ISO-8859-1. Often, the term "Latin-1" (or "Latin1") is used as an equivalent for ISO-8859-1. But some people treat "Latin1" as referring just to the characters in the range 128 through 255, or sometimes from 160 through 255. This documentation uses "Latin1" and "Latin-1" to refer to all 256 characters.
Note that Perl can be compiled and run under either ASCII or EBCDIC (Seeperlebcdic). Most of the documentation (and even comments in the code) ignore the EBCDIC possibility. For almost all purposes the differences are transparent. As an example, under EBCDIC, instead of UTF-8, UTF-EBCDIC is used to encode Unicode strings, and so whenever this documentation refers toutf8 (and variants of that name, including in function names), it also (essentially transparently) meansUTF-EBCDIC. But the ordinals of characters differ between ASCII, EBCDIC, and the UTF- encodings, and a string encoded in UTF-EBCDIC may occupy a different number of bytes than in UTF-8.
The organization of this document is tentative and subject to change. Suggestions and patches welcomeperl5-porters@perl.org.
The sections in this document currently are
The listing below is alphabetical, case insensitive.
AvARRAYReturns a pointer to the AV's internal SV* array.
This is useful for doing pointer arithmetic on the array. If all you need is to look up an array element, then preferav_fetch.
SV** AvARRAY(AV* av)av_clearFrees all the elements of an array, leaving it empty. The XS equivalent of@array = (). See also"av_undef".
Note that it is possible that the actions of a destructor called directly or indirectly by freeing an element of the array could cause the reference count of the array itself to be reduced (e.g. by deleting an entry in the symbol table). So it is a possibility that the AV could have been freed (or even reallocated) on return from the call unless you hold a reference to it.
void av_clear(AV *av)av_countReturns the number of elements in the arrayav. This is the true length of the array, including any undefined elements. It is always the same asav_top_index(av) + 1.
Size_t av_count(AV *av)av_create_and_pushPush an SV onto the end of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.
NOTE:av_create_and_push must be explicitly called asPerl_av_create_and_push with anaTHX_ parameter.
void Perl_av_create_and_push(pTHX_ AV ** const avp, SV * const val)av_create_and_unshift_oneUnshifts an SV onto the beginning of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.
NOTE:av_create_and_unshift_one must be explicitly called asPerl_av_create_and_unshift_one with anaTHX_ parameter.
SV ** Perl_av_create_and_unshift_one(pTHX_ AV ** const avp, SV * const val)av_deleteDeletes the element indexed bykey from the array, makes the element mortal, and returns it. Ifflags equalsG_DISCARD, the element is freed and NULL is returned. NULL is also returned ifkey is out of range.
Perl equivalent:splice(@myarray, $key, 1, undef) (with thesplice in void context ifG_DISCARD is present).
SV * av_delete(AV *av, SSize_t key, I32 flags)av_existsReturns true if the element indexed bykey has been initialized.
This relies on the fact that uninitialized array elements are set toNULL.
Perl equivalent:exists($myarray[$key]).
bool av_exists(AV *av, SSize_t key)av_extendPre-extend an array so that it is capable of storing values at indexes0..key. Thusav_extend(av,99) guarantees that the array can store 100 elements, i.e. thatav_store(av, 0, sv) throughav_store(av, 99, sv) on a plain array will work without any further memory allocation.
If the av argument is a tied array then will call theEXTEND tied array method with an argument of(key+1).
void av_extend(AV *av, SSize_t key)av_fetchReturns the SV at the specified index in the array. Thekey is the index. Iflval is true, you are guaranteed to get a real SV back (in case it wasn't real before), which you can then modify. Check that the return value is non-NULL before dereferencing it to aSV*.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
The rough perl equivalent is$myarray[$key].
SV ** av_fetch(AV *av, SSize_t key, I32 lval)AvFILLSame as"av_top_index" or"av_tindex".
SSize_t AvFILL(AV* av)av_fillSet the highest index in the array to the given number, equivalent to Perl's$#array = $fill;.
The number of elements in the array will befill + 1 afterav_fill() returns. If the array was previously shorter, then the additional elements appended are set to NULL. If the array was longer, then the excess elements are freed.av_fill(av, -1) is the same asav_clear(av).
void av_fill(AV *av, SSize_t fill)av_lenSame as"av_top_index". Note that, unlike what the name implies, it returns the maximum index in the array. This is unlike"sv_len", which returns what you would expect.
To get the true number of elements in the array, instead use"av_count".
SSize_t av_len(AV *av)av_makeCreates a new AV and populates it with a list (**strp, lengthsize) of SVs. A copy is made of each SV, so their refcounts are not changed. The new AV will have a reference count of 1.
Perl equivalent:my @new_array = ($scalar1, $scalar2, $scalar3...);
AV * av_make(SSize_t size, SV **strp)av_popRemoves one SV from the end of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns&PL_sv_undef if the array is empty.
Perl equivalent:pop(@myarray);
SV * av_pop(AV *av)av_pushPushes an SV (transferring control of one reference count) onto the end of the array. The array will grow automatically to accommodate the addition.
Perl equivalent:push @myarray, $val;.
void av_push(AV *av, SV *val)av_push_simpleThis is a cut-down version of av_push that assumes that the array is very straightforward - no magic, not readonly, and AvREAL - and thatkey is not less than -1. This function MUST NOT be used in situations where any of those assumptions may not hold.
Pushes an SV (transferring control of one reference count) onto the end of the array. The array will grow automatically to accommodate the addition.
Perl equivalent:push @myarray, $val;.
void av_push_simple(AV *av, SV *val)av_shiftRemoves one SV from the start of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns&PL_sv_undef if the array is empty.
Perl equivalent:shift(@myarray);
SV * av_shift(AV *av)av_storeStores an SV in an array. The array index is specified askey. The return value will beNULL if the operation failed or if the value did not need to be actually stored within the array (as in the case of tied arrays). Otherwise, it can be dereferenced to get theSV* that was stored there (=val)).
Note that the caller is responsible for suitably incrementing the reference count ofval before the call, and decrementing it if the function returnedNULL.
Approximate Perl equivalent:splice(@myarray, $key, 1, $val).
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
SV ** av_store(AV *av, SSize_t key, SV *val)av_tindexav_top_indexThese behave identically. If the arrayav is empty, these return -1; otherwise they return the maximum value of the indices of all the array elements which are currently defined inav.
They process 'get' magic.
The Perl equivalent for these is$#av.
Use"av_count" to get the number of elements in an array.
SSize_t av_tindex(AV *av)av_undefUndefines the array. The XS equivalent ofundef(@array).
As well as freeing all the elements of the array (likeav_clear()), this also frees the memory used by the av to store its list of scalars.
See"av_clear" for a note about the array possibly being invalid on return.
void av_undef(AV *av)av_unshiftUnshift the given number ofundef values onto the beginning of the array. The array will grow automatically to accommodate the addition.
Perl equivalent:unshift @myarray, ((undef) x $num);
void av_unshift(AV *av, SSize_t num)get_avReturns the AV of the specified Perl global or package array with the given name (so it won't work on lexical variables).flags are passed togv_fetchpv. IfGV_ADD is set and the Perl variable does not exist then it will be created. Ifflags is zero (ignoringSVf_UTF8) and the variable does not exist thenNULL is returned.
Perl equivalent:@{"$name"}.
NOTE: theperl_get_av() form isdeprecated.
AV * get_av(const char *name, I32 flags)newAVnewAV_mortalnewAV_alloc_xnewAV_alloc_xzThese all create a new AV, setting the reference count to 1. If you also know the initial elements of the array with, see"av_make".
As background, an array consists of three things:
A data structure containing information about the array as a whole, such as its size and reference count.
A C language array of pointers to the individual elements. These are treated as pointers to SVs, so all must be castable to SV*.
The individual elements themselves. These could be, for instance, SVs and/or AVs and/or HVs, etc.
An empty array need only have the first data structure, and all these functions create that. They differ in what else they do, as follows:
newAV formThis does nothing beyond creating the whole-array data structure. The Perl equivalent is approximatelymy @array;
This is useful when the minimum size of the array could be zero (perhaps there are likely code paths that will entirely skip using it).
If the array does get used, the pointers data structure will need to be allocated at that time. This will end up being done by"av_extend">, either explicitly:
av_extend(av, len);or implicitly when the first element is stored:
(void)av_store(av, 0, sv);Unused array elements are typically initialized byav_extend.
newAV_mortal formThis also creates the whole-array data structure, but also mortalises it. (That is to say, a reference to the AV is added to thetemps stack.)
newAV_alloc_x formThis effectively does anewAV followed by also allocating (uninitialized) space for the pointers array. This is used when you know ahead of time the likely minimum size of the array. It is more efficient to do this than doing a plainnewAV followed by anav_extend.
Of course the array can be extended later should it become necessary.
size must be at least 1.
newAV_alloc_xz formThis isnewAV_alloc_x, but initializes each pointer in it to NULL. This gives added safety to guard against them being read before being set.
size must be at least 1.
The following examples all result in an array that can fit four elements (indexes 0 .. 3):
AV *av = newAV();av_extend(av, 3);AV *av = newAV_alloc_x(4);AV *av = newAV_alloc_xz(4);In contrast, the following examples allocate an array that is only guaranteed to fit one element without extending:
AV *av = newAV_alloc_x(1);AV *av = newAV_alloc_xz(1);AV * newAV ()AV * newAV_mortal ()AV * newAV_alloc_x (SSize_t size)AV * newAV_alloc_xz(SSize_t size)newAVavCreates a new AV and populates it with values copied from an existing AV. The new AV will have a reference count of 1, and will contain newly created SVs copied from the original SV. The original source will remain unchanged.
Perl equivalent:my @new_array = @existing_array;
AV * newAVav(AV *oav)newAVhvCreates a new AV and populates it with keys and values copied from an existing HV. The new AV will have a reference count of 1, and will contain newly created SVs copied from the original HV. The original source will remain unchanged.
Perl equivalent:my @new_array = %existing_hash;
AV * newAVhv(HV *ohv)NullavDEPRECATED! It is planned to removeNullav from a future release of Perl. Do not use it for new code; remove it from existing code.
Null AV pointer.
(deprecated - use(AV *)NULL instead)
call_argvPerforms a callback to the specified named and package-scoped Perl subroutine withargv (aNULL-terminated array of strings) as arguments. Seeperlcall.
Approximate Perl equivalent:&{"$sub_name"}(@$argv).
NOTE: theperl_call_argv() form isdeprecated.
SSize_t call_argv(const char *sub_name, I32 flags, char **argv)call_methodPerforms a callback to the specified Perl method. The blessed object must be on the stack. Seeperlcall.
NOTE: theperl_call_method() form isdeprecated.
SSize_t call_method(const char *methname, I32 flags)call_pvPerforms a callback to the specified Perl sub. Seeperlcall.
NOTE: theperl_call_pv() form isdeprecated.
SSize_t call_pv(const char *sub_name, I32 flags)call_svPerforms a callback to the Perl sub specified by the SV.
If neither theG_METHOD norG_METHOD_NAMED flag is supplied, the SV may be any of a CV, a GV, a reference to a CV, a reference to a GV orSvPV(sv) will be used as the name of the sub to call.
If theG_METHOD flag is supplied, the SV may be a reference to a CV orSvPV(sv) will be used as the name of the method to call.
If theG_METHOD_NAMED flag is supplied,SvPV(sv) will be used as the name of the method to call.
Some other values are treated specially for internal use and should not be depended on.
Seeperlcall.
NOTE: theperl_call_sv() form isdeprecated.
SSize_t call_sv(SV *sv, I32 flags)ENTER_with_nameSame as"ENTER", but when debugging is enabled it also associates the given literal string with the new scope.
ENTER_with_name("name");eval_pvTells Perl toeval the given string in scalar context and return an SV* result.
NOTE: theperl_eval_pv() form isdeprecated.
SV * eval_pv(const char *p, I32 croak_on_error)eval_svTells Perl toeval the string in the SV. It supports the same flags ascall_sv, with the obvious exception ofG_EVAL. Seeperlcall.
TheG_RETHROW flag can be used if you only need eval_sv() to execute code specified by a string, but not catch any errors.
By default the code is compiled and executed with the default hints, such as strict and features. SetG_USEHINTS in flags to use the current hints fromPL_curcop.
NOTE: theperl_eval_sv() form isdeprecated.
SSize_t eval_sv(SV *sv, I32 flags)FREETMPSClosing bracket for temporaries on a callback. See"SAVETMPS" andperlcall.
FREETMPS;GIMMEDEPRECATED! It is planned to removeGIMME from a future release of Perl. Do not use it for new code; remove it from existing code.
A backward-compatible version ofGIMME_V which can only returnG_SCALAR orG_LIST; in a void context, it returnsG_SCALAR. Deprecated. UseGIMME_V instead.
U32 GIMMEGIMME_VThe XSUB-writer's equivalent to Perl'swantarray. ReturnsG_VOID,G_SCALAR orG_LIST for void, scalar or list context, respectively. Seeperlcall for a usage example.
U32 GIMME_Vis_lvalue_subReturns non-zero if the sub calling this function is being called in an lvalue context. Returns 0 otherwise.
I32 is_lvalue_sub()LEAVE_with_nameSame as"LEAVE", but when debugging is enabled it first checks that the scope has the given name.name must be a literal string.
LEAVE_with_name("name");mortal_destructor_svThis function arranges for either a Perl code reference, or a C function reference to be called at theend of the current statement.
Thecoderef argument determines the type of function that will be called. If it isSvROK() it is assumed to be a reference to a CV and will arrange for the coderef to be called. If it is not SvROK() then it is assumed to be aSvIV() which isSvIOK() whose value is a pointer to a C function of typeDESTRUCTORFUNC_t created usingPTR2INT(). Either way theargs parameter will be provided to the callback as a parameter, although the rules for doing so differ between the Perl and C mode. Normally this function is only used directly for the Perl case and the wrappermortal_destructor_x() is used for the C function case.
When operating in Perl callback mode theargs parameter may be NULL in which case the code reference is called with no arguments, otherwise if it is an AV (SvTYPE(args) == SVt_PVAV) then the contents of the AV will be used as the arguments to the code reference, and if it is any other type then theargs SV will be provided as a single argument to the code reference.
When operating in a C callback mode theargs parameter will be passed directly to the C function as avoid * pointer. No additional processing of the argument will be peformed, and it is the callers responsibility to free theargs parameter if necessary.
Be aware that there is a signficant difference in timing between theend of the current statement and theend of the current pseudo block. If you are looking for a mechanism to trigger a function at the end of thecurrent pseudo block you should look at"SAVEDESTRUCTOR_X" in perlapi instead of this function.
void mortal_destructor_sv(SV *coderef, SV *args)save_aelemsave_aelem_flagsThese each arrange for the value of the array elementav[idx] to be restored at the end of the enclosingpseudo-block.
Insave_aelem, the SV at C**sptr> will be replaced by a newundef scalar. That scalar will inherit any magic from the original**sptr, and any 'set' magic will be processed.
Insave_aelem_flags,SAVEf_KEEPOLDELEM being set inflags causes the function to forgo all that: the scalar at**sptr is untouched. IfSAVEf_KEEPOLDELEM is not set, the SV at C**sptr> will be replaced by a newundef scalar. That scalar will inherit any magic from the original**sptr. Any 'set' magic will be processed if and only ifSAVEf_SETMAGIC is set in inflags.
void save_aelem (AV *av, SSize_t idx, SV **sptr)void save_aelem_flags(AV *av, SSize_t idx, SV **sptr, const U32 flags)save_helemsave_helem_flagsThese each arrange for the value of the hash element (in Perlish terms)$hv{key}] to be restored at the end of the enclosingpseudo-block.
Insave_helem, the SV at C**sptr> will be replaced by a newundef scalar. That scalar will inherit any magic from the original**sptr, and any 'set' magic will be processed.
Insave_helem_flags,SAVEf_KEEPOLDELEM being set inflags causes the function to forgo all that: the scalar at**sptr is untouched. IfSAVEf_KEEPOLDELEM is not set, the SV at C**sptr> will be replaced by a newundef scalar. That scalar will inherit any magic from the original**sptr. Any 'set' magic will be processed if and only ifSAVEf_SETMAGIC is set in inflags.
void save_helem (HV *hv, SV *key, SV **sptr)void save_helem_flags(HV *hv, SV *key, SV **sptr, const U32 flags)SAVETMPSOpening bracket for temporaries on a callback. See"FREETMPS" andperlcall.
SAVETMPS;cBOOLCast-to-bool. When Perl was able to be compiled on pre-C99 compilers, a(bool) cast didn't necessarily do the right thing, so this macro was created (and made somewhat complicated to work around bugs in old compilers). Now, many years later, and C99 is used, this is no longer required, but is kept for backwards compatibility.
bool cBOOL(bool expr)I_VCast an NV to IV while avoiding undefined C behavior
IV I_V(NV what)I_32Cast an NV to I32 while avoiding undefined C behavior
I32 I_32(NV what)U_VCast an NV to UV while avoiding undefined C behavior
UV U_V(NV what)U_32Cast an NV to U32 while avoiding undefined C behavior
U32 U_32(NV what)Perl uses "full" Unicode case mappings. This means that converting a single character to another case may result in a sequence of more than one character. For example, the uppercase ofß (LATIN SMALL LETTER SHARP S) is the two character sequenceSS. This presents some complications The lowercase of all characters in the range 0..255 is a single character, and thus"toLOWER_L1" is furnished. But,toUPPER_L1 can't exist, as it couldn't return a valid result for all legal inputs. Instead"toUPPER_uvchr" has an API that does allow every possible legal result to be returned.) Likewise no other function that is crippled by not being able to give the correct results for the full range of possible inputs has been implemented here.
toFOLDtoFOLD_AtoFOLD_utf8toFOLD_utf8_safetoFOLD_uvchrThese all return the foldcase of a character. "foldcase" is an internal case for/i pattern matching. If the foldcase of character A and the foldcase of character B are the same, they match caselessly; otherwise they don't.
The differences in the forms are what domain they operate on, and whether the input is specified as a code point (those forms with acp parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the argumentsp .. e - 1.
toFOLD andtoFOLD_A are synonyms of each other. They return the foldcase of any ASCII-range code point. In this range, the foldcase is identical to the lowercase. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is notoFOLD_L1 nortoFOLD_LATIN1 as the foldcase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead usetoFOLD_uvchr.
toFOLD_uvchr returns the foldcase of any Unicode code point. The return value is identical to that oftoFOLD_A for input code points in the ASCII range. The foldcase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning ats, and its length in bytes into*lenp. The caller must have mades large enough to contain at leastUTF8_MAXBYTES_CASE+1 bytes to avoid possible overflow.
NOTE: the foldcase of a code point may be more than one code point. The return value of this function is only the first of these. The entire foldcase is returned ins. To determine if the result is more than a single code point, you can do something like this:
uc = toFOLD_uvchr(cp, s, &len);if (len > UTF8SKIP(s)) { is multiple code points }else { is a single code point }toFOLD_utf8 andtoFOLD_utf8_safe are synonyms of each other. The only difference between these andtoFOLD_uvchr is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting atp, withe pointing to one byte beyond its end. Thep buffer may certainly contain more than one code point; but only the first one (up throughe - 1) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toFOLD (UV cp)UV toFOLD_A (UV cp)UV toFOLD_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)UV toFOLD_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)UV toFOLD_uvchr (UV cp, U8* s, STRLEN* lenp)toLOWERtoLOWER_AtoLOWER_LATIN1toLOWER_LCtoLOWER_L1toLOWER_utf8toLOWER_utf8_safetoLOWER_uvchrThese all return the lowercase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with acp parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the argumentsp .. e - 1.
toLOWER andtoLOWER_A are synonyms of each other. They return the lowercase of any uppercase ASCII-range code point. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
toLOWER_L1 andtoLOWER_LATIN1 are synonyms of each other. They behave identically astoLOWER for ASCII-range input. But additionally will return the lowercase of any uppercase code point in the entire 0..255 range, assuming a Latin-1 encoding (or the EBCDIC equivalent on such platforms).
toLOWER_LC returns the lowercase of the input code point according to the rules of the current POSIX locale. Input code points outside the range 0..255 are returned unchanged.
toLOWER_uvchr returns the lowercase of any Unicode code point. The return value is identical to that oftoLOWER_L1 for input code points in the 0..255 range. The lowercase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning ats, and its length in bytes into*lenp. The caller must have mades large enough to contain at leastUTF8_MAXBYTES_CASE+1 bytes to avoid possible overflow.
NOTE: the lowercase of a code point may be more than one code point. The return value of this function is only the first of these. The entire lowercase is returned ins. To determine if the result is more than a single code point, you can do something like this:
uc = toLOWER_uvchr(cp, s, &len);if (len > UTF8SKIP(s)) { is multiple code points }else { is a single code point }toLOWER_utf8 andtoLOWER_utf8_safe are synonyms of each other. The only difference between these andtoLOWER_uvchr is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting atp, withe pointing to one byte beyond its end. Thep buffer may certainly contain more than one code point; but only the first one (up throughe - 1) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toLOWER (UV cp)UV toLOWER_A (UV cp)UV toLOWER_LATIN1 (UV cp)UV toLOWER_LC (UV cp)UV toLOWER_L1 (UV cp)UV toLOWER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)UV toLOWER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)UV toLOWER_uvchr (UV cp, U8* s, STRLEN* lenp)toTITLEtoTITLE_AtoTITLE_utf8toTITLE_utf8_safetoTITLE_uvchrThese all return the titlecase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with acp parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the argumentsp .. e - 1.
toTITLE andtoTITLE_A are synonyms of each other. They return the titlecase of any lowercase ASCII-range code point. In this range, the titlecase is identical to the uppercase. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is notoTITLE_L1 nortoTITLE_LATIN1 as the titlecase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead usetoTITLE_uvchr.
toTITLE_uvchr returns the titlecase of any Unicode code point. The return value is identical to that oftoTITLE_A for input code points in the ASCII range. The titlecase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning ats, and its length in bytes into*lenp. The caller must have mades large enough to contain at leastUTF8_MAXBYTES_CASE+1 bytes to avoid possible overflow.
NOTE: the titlecase of a code point may be more than one code point. The return value of this function is only the first of these. The entire titlecase is returned ins. To determine if the result is more than a single code point, you can do something like this:
uc = toTITLE_uvchr(cp, s, &len);if (len > UTF8SKIP(s)) { is multiple code points }else { is a single code point }toTITLE_utf8 andtoTITLE_utf8_safe are synonyms of each other. The only difference between these andtoTITLE_uvchr is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting atp, withe pointing to one byte beyond its end. Thep buffer may certainly contain more than one code point; but only the first one (up throughe - 1) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toTITLE (UV cp)UV toTITLE_A (UV cp)UV toTITLE_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)UV toTITLE_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)UV toTITLE_uvchr (UV cp, U8* s, STRLEN* lenp)toUPPERtoUPPER_AtoUPPER_utf8toUPPER_utf8_safetoUPPER_uvchrThese all return the uppercase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with acp parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the argumentsp .. e - 1.
toUPPER andtoUPPER_A are synonyms of each other. They return the uppercase of any lowercase ASCII-range code point. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is notoUPPER_L1 nortoUPPER_LATIN1 as the uppercase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead usetoUPPER_uvchr.
toUPPER_uvchr returns the uppercase of any Unicode code point. The return value is identical to that oftoUPPER_A for input code points in the ASCII range. The uppercase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning ats, and its length in bytes into*lenp. The caller must have mades large enough to contain at leastUTF8_MAXBYTES_CASE+1 bytes to avoid possible overflow.
NOTE: the uppercase of a code point may be more than one code point. The return value of this function is only the first of these. The entire uppercase is returned ins. To determine if the result is more than a single code point, you can do something like this:
uc = toUPPER_uvchr(cp, s, &len);if (len > UTF8SKIP(s)) { is multiple code points }else { is a single code point }toUPPER_utf8 andtoUPPER_utf8_safe are synonyms of each other. The only difference between these andtoUPPER_uvchr is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting atp, withe pointing to one byte beyond its end. Thep buffer may certainly contain more than one code point; but only the first one (up throughe - 1) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toUPPER (UV cp)UV toUPPER_A (UV cp)UV toUPPER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)UV toUPPER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)UV toUPPER_uvchr (UV cp, U8* s, STRLEN* lenp)This section is about functions (really macros) that classify characters into types, such as punctuation versus alphabetic, etc. Most of these are analogous to regular expression character classes. (See"POSIX Character Classes" in perlrecharclass.) There are several variants for each class. (Not all macros have all variants; each item below lists the ones valid for it.) None are affected byuse bytes, and only the ones withLC in the name are affected by the current locale.
The base function, e.g.,isALPHA(), takes any signed or unsigned value, treating it as a code point, and returns a boolean as to whether or not the character represented by it is (or on non-ASCII platforms, corresponds to) an ASCII character in the named class based on platform, Unicode, and Perl rules. If the input is a number that doesn't fit in an octet, FALSE is returned.
VariantisFOO_A (e.g.,isALPHA_A()) is identical to the base function with no suffix"_A". This variant is used to emphasize by its name that only ASCII-range characters can return TRUE.
VariantisFOO_L1 imposes the Latin-1 (or EBCDIC equivalent) character set onto the platform. That is, the code points that are ASCII are unaffected, since ASCII is a subset of Latin-1. But the non-ASCII code points are treated as if they are Latin-1 characters. For example,isWORDCHAR_L1() will return true when called with the code point 0xDF, which is a word character in both ASCII and EBCDIC (though it represents different characters in each). If the input is a number that doesn't fit in an octet, FALSE is returned. (Perl's documentation uses a colloquial definition of Latin-1, to include all code points below 256.)
VariantisFOO_uvchr is exactly like theisFOO_L1 variant, for inputs below 256, but if the code point is larger than 255, Unicode rules are used to determine if it is in the character class. For example,isWORDCHAR_uvchr(0x100) returns TRUE, since 0x100 is LATIN CAPITAL LETTER A WITH MACRON in Unicode, and is a word character.
VariantsisFOO_utf8 andisFOO_utf8_safe are likeisFOO_uvchr, but are used for UTF-8 encoded strings. The two forms are different names for the same thing. Each call to one of these classifies the first character of the string starting atp. The second parameter,e, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. Although both variants are identical, the suffix_safe in one name emphasizes that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
VariantisFOO_LC is like theisFOO_A andisFOO_L1 variants, but the result is based on the current locale, which is whatLC in the name stands for. If Perl can determine that the current locale is a UTF-8 locale, it uses the published Unicode rules; otherwise, it uses the C library function that gives the named classification. For example,isDIGIT_LC() when not in a UTF-8 locale returns the result of callingisdigit(). FALSE is always returned if the input won't fit into an octet. On some platforms where the C library function is known to be defective, Perl changes its result to follow the POSIX standard's rules.
VariantisFOO_LC_uvchr acts exactly likeisFOO_LC for inputs less than 256, but for larger ones it returns the Unicode classification of the code point.
VariantsisFOO_LC_utf8 andisFOO_LC_utf8_safe are likeisFOO_LC_uvchr, but are used for UTF-8 encoded strings. The two forms are different names for the same thing. Each call to one of these classifies the first character of the string starting atp. The second parameter,e, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. Although both variants are identical, the suffix_safe in one name emphasizes that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
isALNUMisALNUM_AisALNUM_LCisALNUM_LC_uvchrThese are each a synonym for their respectively named"isWORDCHAR" variant.
They are provided for backward compatibility, even though a word character includes more than the standard C language meaning of alphanumeric. To get the C language definition, use the corresponding"isALPHANUMERIC" variant.
bool isALNUM(UV ch)isALNUMCisALNUMC_AisALNUMC_LCisALNUMC_LC_uvchrisALNUMC_L1These are discouraged, backward compatibility macros for"isALPHANUMERIC". That is, each returns a boolean indicating whether the specified character is one of[A-Za-z0-9], analogous tom/[[:alnum:]]/.
TheC suffix in the names was meant to indicate that they correspond to the C languageisalnum(3).
bool isALNUMC(UV ch)isALPHAisALPHA_AisALPHA_LCisALPHA_LC_utf8_safeisALPHA_LC_uvchrisALPHA_L1isALPHA_utf8isALPHA_utf8_safeisALPHA_uvchrReturns a boolean indicating whether the specified input is one of[A-Za-z], analogous tom/[[:alpha:]]/. See thetop of this section for an explanation of the variants.
bool isALPHA (UV ch)bool isALPHA_A (UV ch)bool isALPHA_LC (UV ch)bool isALPHA_LC_utf8_safe(U8 * s, U8 *end)bool isALPHA_LC_uvchr (UV ch)bool isALPHA_L1 (UV ch)bool isALPHA_utf8 (U8 * s, U8 * end)bool isALPHA_utf8_safe (U8 * s, U8 * end)bool isALPHA_uvchr (UV ch)isALPHANUMERICisALPHANUMERIC_AisALPHANUMERIC_LCisALPHANUMERIC_LC_utf8_safeisALPHANUMERIC_LC_uvchrisALPHANUMERIC_L1isALPHANUMERIC_utf8isALPHANUMERIC_utf8_safeisALPHANUMERIC_uvchrReturns a boolean indicating whether the specified character is one of[A-Za-z0-9], analogous tom/[[:alnum:]]/. See thetop of this section for an explanation of the variants.
bool isALPHANUMERIC (UV ch)bool isALPHANUMERIC_A (UV ch)bool isALPHANUMERIC_LC (UV ch)bool isALPHANUMERIC_LC_utf8_safe(U8 * s, U8 *end)bool isALPHANUMERIC_LC_uvchr (UV ch)bool isALPHANUMERIC_L1 (UV ch)bool isALPHANUMERIC_utf8 (U8 * s, U8 * end)bool isALPHANUMERIC_utf8_safe (U8 * s, U8 * end)bool isALPHANUMERIC_uvchr (UV ch)isASCIIisASCII_AisASCII_LCisASCII_LC_utf8_safeisASCII_LC_uvchrisASCII_L1isASCII_utf8isASCII_utf8_safeisASCII_uvchrReturns a boolean indicating whether the specified character is one of the 128 characters in the ASCII character set, analogous tom/[[:ascii:]]/. On non-ASCII platforms, it returns TRUE iff this character corresponds to an ASCII character. VariantsisASCII_A() andisASCII_L1() are identical toisASCII(). See thetop of this section for an explanation of the variants. Note, however, that some platforms do not have the C library routineisascii(). In these cases, the variants whose names containLC are the same as the corresponding ones without.
Also note, that because all ASCII characters are UTF-8 invariant (meaning they have the exact same representation (always a single byte) whether encoded in UTF-8 or not),isASCII will give the correct results when called with any byte in any string encoded or not in UTF-8. And similarlyisASCII_utf8 andisASCII_utf8_safe will work properly on any string encoded or not in UTF-8.
bool isASCII (UV ch)bool isASCII_A (UV ch)bool isASCII_LC (UV ch)bool isASCII_LC_utf8_safe(U8 * s, U8 *end)bool isASCII_LC_uvchr (UV ch)bool isASCII_L1 (UV ch)bool isASCII_utf8 (U8 * s, U8 * end)bool isASCII_utf8_safe (U8 * s, U8 * end)bool isASCII_uvchr (UV ch)isBLANKisBLANK_AisBLANK_LCisBLANK_LC_utf8_safeisBLANK_LC_uvchrisBLANK_L1isBLANK_utf8isBLANK_utf8_safeisBLANK_uvchrReturns a boolean indicating whether the specified character is a character considered to be a blank, analogous tom/[[:blank:]]/. See thetop of this section for an explanation of the variants. Note, however, that some platforms do not have the C library routineisblank(). In these cases, the variants whose names containLC are the same as the corresponding ones without.
bool isBLANK (UV ch)bool isBLANK_A (UV ch)bool isBLANK_LC (UV ch)bool isBLANK_LC_utf8_safe(U8 * s, U8 *end)bool isBLANK_LC_uvchr (UV ch)bool isBLANK_L1 (UV ch)bool isBLANK_utf8 (U8 * s, U8 * end)bool isBLANK_utf8_safe (U8 * s, U8 * end)bool isBLANK_uvchr (UV ch)isCNTRLisCNTRL_AisCNTRL_LCisCNTRL_LC_utf8_safeisCNTRL_LC_uvchrisCNTRL_L1isCNTRL_utf8isCNTRL_utf8_safeisCNTRL_uvchrReturns a boolean indicating whether the specified character is a control character, analogous tom/[[:cntrl:]]/. See thetop of this section for an explanation of the variants. On EBCDIC platforms, you almost always want to use theisCNTRL_L1 variant.
bool isCNTRL (UV ch)bool isCNTRL_A (UV ch)bool isCNTRL_LC (UV ch)bool isCNTRL_LC_utf8_safe(U8 * s, U8 *end)bool isCNTRL_LC_uvchr (UV ch)bool isCNTRL_L1 (UV ch)bool isCNTRL_utf8 (U8 * s, U8 * end)bool isCNTRL_utf8_safe (U8 * s, U8 * end)bool isCNTRL_uvchr (UV ch)isDIGITisDIGIT_AisDIGIT_LCisDIGIT_LC_utf8_safeisDIGIT_LC_uvchrisDIGIT_L1isDIGIT_utf8isDIGIT_utf8_safeisDIGIT_uvchrReturns a boolean indicating whether the specified character is a digit, analogous tom/[[:digit:]]/. VariantsisDIGIT_A andisDIGIT_L1 are identical toisDIGIT. See thetop of this section for an explanation of the variants.
bool isDIGIT (UV ch)bool isDIGIT_A (UV ch)bool isDIGIT_LC (UV ch)bool isDIGIT_LC_utf8_safe(U8 * s, U8 *end)bool isDIGIT_LC_uvchr (UV ch)bool isDIGIT_L1 (UV ch)bool isDIGIT_utf8 (U8 * s, U8 * end)bool isDIGIT_utf8_safe (U8 * s, U8 * end)bool isDIGIT_uvchr (UV ch)isGRAPHisGRAPH_AisGRAPH_LCisGRAPH_LC_utf8_safeisGRAPH_LC_uvchrisGRAPH_L1isGRAPH_utf8isGRAPH_utf8_safeisGRAPH_uvchrReturns a boolean indicating whether the specified character is a graphic character, analogous tom/[[:graph:]]/. See thetop of this section for an explanation of the variants.
bool isGRAPH (UV ch)bool isGRAPH_A (UV ch)bool isGRAPH_LC (UV ch)bool isGRAPH_LC_utf8_safe(U8 * s, U8 *end)bool isGRAPH_LC_uvchr (UV ch)bool isGRAPH_L1 (UV ch)bool isGRAPH_utf8 (U8 * s, U8 * end)bool isGRAPH_utf8_safe (U8 * s, U8 * end)bool isGRAPH_uvchr (UV ch)isIDCONTisIDCONT_AisIDCONT_LCisIDCONT_LC_utf8_safeisIDCONT_LC_uvchrisIDCONT_L1isIDCONT_utf8isIDCONT_utf8_safeisIDCONT_uvchrReturns a boolean indicating whether the specified character can be the second or succeeding character of an identifier. This is very close to, but not quite the same as the official Unicode propertyXID_Continue. The difference is that this returns true only if the input character also matches"isWORDCHAR". See thetop of this section for an explanation of the variants.
bool isIDCONT (UV ch)bool isIDCONT_A (UV ch)bool isIDCONT_LC (UV ch)bool isIDCONT_LC_utf8_safe(U8 * s, U8 *end)bool isIDCONT_LC_uvchr (UV ch)bool isIDCONT_L1 (UV ch)bool isIDCONT_utf8 (U8 * s, U8 * end)bool isIDCONT_utf8_safe (U8 * s, U8 * end)bool isIDCONT_uvchr (UV ch)isIDFIRSTisIDFIRST_AisIDFIRST_LCisIDFIRST_LC_utf8_safeisIDFIRST_LC_uvchrisIDFIRST_L1isIDFIRST_utf8isIDFIRST_utf8_safeisIDFIRST_uvchrReturns a boolean indicating whether the specified character can be the first character of an identifier. This is very close to, but not quite the same as the official Unicode propertyXID_Start. The difference is that this returns true only if the input character also matches"isWORDCHAR". See thetop of this section for an explanation of the variants.
bool isIDFIRST (UV ch)bool isIDFIRST_A (UV ch)bool isIDFIRST_LC (UV ch)bool isIDFIRST_LC_utf8_safe(U8 * s, U8 *end)bool isIDFIRST_LC_uvchr (UV ch)bool isIDFIRST_L1 (UV ch)bool isIDFIRST_utf8 (U8 * s, U8 * end)bool isIDFIRST_utf8_safe (U8 * s, U8 * end)bool isIDFIRST_uvchr (UV ch)isLOWERisLOWER_AisLOWER_LCisLOWER_LC_utf8_safeisLOWER_LC_uvchrisLOWER_L1isLOWER_utf8isLOWER_utf8_safeisLOWER_uvchrReturns a boolean indicating whether the specified character is a lowercase character, analogous tom/[[:lower:]]/. See thetop of this section for an explanation of the variants
bool isLOWER (UV ch)bool isLOWER_A (UV ch)bool isLOWER_LC (UV ch)bool isLOWER_LC_utf8_safe(U8 * s, U8 *end)bool isLOWER_LC_uvchr (UV ch)bool isLOWER_L1 (UV ch)bool isLOWER_utf8 (U8 * s, U8 * end)bool isLOWER_utf8_safe (U8 * s, U8 * end)bool isLOWER_uvchr (UV ch)isOCTALisOCTAL_AisOCTAL_L1Returns a boolean indicating whether the specified character is an octal digit, [0-7]. The only two variants areisOCTAL_A andisOCTAL_L1; each is identical toisOCTAL.
bool isOCTAL(UV ch)isPRINTisPRINT_AisPRINT_LCisPRINT_LC_utf8_safeisPRINT_LC_uvchrisPRINT_L1isPRINT_utf8isPRINT_utf8_safeisPRINT_uvchrReturns a boolean indicating whether the specified character is a printable character, analogous tom/[[:print:]]/. See thetop of this section for an explanation of the variants.
bool isPRINT (UV ch)bool isPRINT_A (UV ch)bool isPRINT_LC (UV ch)bool isPRINT_LC_utf8_safe(U8 * s, U8 *end)bool isPRINT_LC_uvchr (UV ch)bool isPRINT_L1 (UV ch)bool isPRINT_utf8 (U8 * s, U8 * end)bool isPRINT_utf8_safe (U8 * s, U8 * end)bool isPRINT_uvchr (UV ch)isPSXSPCisPSXSPC_AisPSXSPC_LCisPSXSPC_LC_utf8_safeisPSXSPC_LC_uvchrisPSXSPC_L1isPSXSPC_utf8isPSXSPC_utf8_safeisPSXSPC_uvchr(short for Posix Space) Starting in 5.18, this is identical in all its forms to the correspondingisSPACE() macros. The locale forms of this macro are identical to their correspondingisSPACE() forms in all Perl releases. In releases prior to 5.18, the non-locale forms differ from theirisSPACE() forms only in that theisSPACE() forms don't match a Vertical Tab, and theisPSXSPC() forms do. Otherwise they are identical. Thus this macro is analogous to whatm/[[:space:]]/ matches in a regular expression. See thetop of this section for an explanation of the variants.
bool isPSXSPC (UV ch)bool isPSXSPC_A (UV ch)bool isPSXSPC_LC (UV ch)bool isPSXSPC_LC_utf8_safe(U8 * s, U8 *end)bool isPSXSPC_LC_uvchr (UV ch)bool isPSXSPC_L1 (UV ch)bool isPSXSPC_utf8 (U8 * s, U8 * end)bool isPSXSPC_utf8_safe (U8 * s, U8 * end)bool isPSXSPC_uvchr (UV ch)isPUNCTisPUNCT_AisPUNCT_LCisPUNCT_LC_utf8_safeisPUNCT_LC_uvchrisPUNCT_L1isPUNCT_utf8isPUNCT_utf8_safeisPUNCT_uvchrReturns a boolean indicating whether the specified character is a punctuation character, analogous tom/[[:punct:]]/. Note that the definition of what is punctuation isn't as straightforward as one might desire. See"POSIX Character Classes" in perlrecharclass for details. See thetop of this section for an explanation of the variants.
bool isPUNCT (UV ch)bool isPUNCT_A (UV ch)bool isPUNCT_LC (UV ch)bool isPUNCT_LC_utf8_safe(U8 * s, U8 *end)bool isPUNCT_LC_uvchr (UV ch)bool isPUNCT_L1 (UV ch)bool isPUNCT_utf8 (U8 * s, U8 * end)bool isPUNCT_utf8_safe (U8 * s, U8 * end)bool isPUNCT_uvchr (UV ch)isSPACEisSPACE_AisSPACE_LCisSPACE_LC_utf8_safeisSPACE_LC_uvchrisSPACE_L1isSPACE_utf8isSPACE_utf8_safeisSPACE_uvchrReturns a boolean indicating whether the specified character is a whitespace character. This is analogous to whatm/\s/ matches in a regular expression. Starting in Perl 5.18 this also matches whatm/[[:space:]]/ does. Prior to 5.18, only the locale forms of this macro (the ones withLC in their names) matched precisely whatm/[[:space:]]/ does. In those releases, the only difference, in the non-locale variants, was thatisSPACE() did not match a vertical tab. (See"isPSXSPC" for a macro that matches a vertical tab in all releases.) See thetop of this section for an explanation of the variants.
bool isSPACE (UV ch)bool isSPACE_A (UV ch)bool isSPACE_LC (UV ch)bool isSPACE_LC_utf8_safe(U8 * s, U8 *end)bool isSPACE_LC_uvchr (UV ch)bool isSPACE_L1 (UV ch)bool isSPACE_utf8 (U8 * s, U8 * end)bool isSPACE_utf8_safe (U8 * s, U8 * end)bool isSPACE_uvchr (UV ch)isUPPERisUPPER_AisUPPER_LCisUPPER_LC_utf8_safeisUPPER_LC_uvchrisUPPER_L1isUPPER_utf8isUPPER_utf8_safeisUPPER_uvchrReturns a boolean indicating whether the specified character is an uppercase character, analogous tom/[[:upper:]]/. See thetop of this section for an explanation of the variants.
bool isUPPER (UV ch)bool isUPPER_A (UV ch)bool isUPPER_LC (UV ch)bool isUPPER_LC_utf8_safe(U8 * s, U8 *end)bool isUPPER_LC_uvchr (UV ch)bool isUPPER_L1 (UV ch)bool isUPPER_utf8 (U8 * s, U8 * end)bool isUPPER_utf8_safe (U8 * s, U8 * end)bool isUPPER_uvchr (UV ch)isWORDCHARisWORDCHAR_AisWORDCHAR_LCisWORDCHAR_LC_utf8_safeisWORDCHAR_LC_uvchrisWORDCHAR_L1isWORDCHAR_utf8isWORDCHAR_utf8_safeisWORDCHAR_uvchrReturns a boolean indicating whether the specified character is a character that is a word character, analogous to whatm/\w/ andm/[[:word:]]/ match in a regular expression. A word character is an alphabetic character, a decimal digit, a connecting punctuation character (such as an underscore), or a "mark" character that attaches to one of those (like some sort of accent).
See thetop of this section for an explanation of the variants.
isWORDCHAR_A,isWORDCHAR_L1,isWORDCHAR_uvchr,isWORDCHAR_LC,isWORDCHAR_LC_uvchr,isWORDCHAR_LC_utf8, andisWORDCHAR_LC_utf8_safe are also as described there, but additionally include the platform's native underscore.
bool isWORDCHAR (UV ch)bool isWORDCHAR_A (UV ch)bool isWORDCHAR_LC (UV ch)bool isWORDCHAR_LC_utf8_safe(U8 * s, U8 *end)bool isWORDCHAR_LC_uvchr (UV ch)bool isWORDCHAR_L1 (UV ch)bool isWORDCHAR_utf8 (U8 * s, U8 * end)bool isWORDCHAR_utf8_safe (U8 * s, U8 * end)bool isWORDCHAR_uvchr (UV ch)isXDIGITisXDIGIT_AisXDIGIT_LCisXDIGIT_LC_utf8_safeisXDIGIT_LC_uvchrisXDIGIT_L1isXDIGIT_utf8isXDIGIT_utf8_safeisXDIGIT_uvchrReturns a boolean indicating whether the specified character is a hexadecimal digit. In the ASCII range these are[0-9A-Fa-f]. VariantsisXDIGIT_A() andisXDIGIT_L1() are identical toisXDIGIT(). See thetop of this section for an explanation of the variants.
bool isXDIGIT (UV ch)bool isXDIGIT_A (UV ch)bool isXDIGIT_LC (UV ch)bool isXDIGIT_LC_utf8_safe(U8 * s, U8 *end)bool isXDIGIT_LC_uvchr (UV ch)bool isXDIGIT_L1 (UV ch)bool isXDIGIT_utf8 (U8 * s, U8 * end)bool isXDIGIT_utf8_safe (U8 * s, U8 * end)bool isXDIGIT_uvchr (UV ch)CPPLASTThis symbol is intended to be used along withCPPRUN in the same manner symbolCPPMINUS is used withCPPSTDIN. It contains either "-" or "".
CPPMINUSThis symbol contains the second part of the string which will invoke the C preprocessor on the standard input and produce to standard output. This symbol will have the value "-" ifCPPSTDIN needs a minus to specify standard input, otherwise the value is "".
CPPRUNThis symbol contains the string which will invoke a C preprocessor on the standard input and produce to standard output. It needs to end withCPPLAST, after all other preprocessor flags have been specified. The main difference withCPPSTDIN is that this program will never be a pointer to a shell wrapper, i.e. it will be empty if no preprocessor is available directly to the user. Note that it may well be different from the preprocessor used to compile the C program.
CPPSTDINThis symbol contains the first part of the string which will invoke the C preprocessor on the standard input and produce to standard output. Typical value of "cc -E" or "/lib/cpp", but it can also call a wrapper. See"CPPRUN".
HASATTRIBUTE_ALWAYS_INLINECan we handleGCC attribute for functions that should always be inlined.
HASATTRIBUTE_DEPRECATEDCan we handleGCC attribute for marking deprecatedAPIs
HASATTRIBUTE_FORMATCan we handleGCC attribute for checking printf-style formats
HASATTRIBUTE_NONNULLCan we handleGCC attribute for nonnull function parms.
HASATTRIBUTE_NORETURNCan we handleGCC attribute for functions that do not return
HASATTRIBUTE_PURECan we handleGCC attribute for pure functions
HASATTRIBUTE_UNUSEDCan we handleGCC attribute for unused variables and arguments
HASATTRIBUTE_VISIBILITYCan we handleGCC attribute for functions that should have a different visibility.
HASATTRIBUTE_WARN_UNUSED_RESULTCan we handleGCC attribute for warning on unused results
HAS_BUILTIN_ADD_OVERFLOWThis symbol, if defined, indicates that the compiler supports__builtin_add_overflow for adding integers with overflow checks.
HAS_BUILTIN_CHOOSE_EXPRCan we handleGCC builtin for compile-time ternary-like expressions
HAS_BUILTIN_EXPECTCan we handleGCC builtin for telling that certain values are more likely
HAS_BUILTIN_MUL_OVERFLOWThis symbol, if defined, indicates that the compiler supports__builtin_mul_overflow for multiplying integers with overflow checks.
HAS_BUILTIN_SUB_OVERFLOWThis symbol, if defined, indicates that the compiler supports__builtin_sub_overflow for subtracting integers with overflow checks.
HAS_C99_VARIADIC_MACROSIf defined, the compiler supports C99 variadic macros.
HAS_STATIC_INLINEThis symbol, if defined, indicates that the C compiler supports C99-style static inline. That is, the function can't be called from another translation unit.
MEM_ALIGNBYTESThis symbol contains the number of bytes required to align a double, or a long double when applicable. Usual values are 2, 4 and 8. The default is eight, for safety. For cross-compiling or multiarch support, Configure will set a minimum of 8.
PERL_STATIC_INLINEThis symbol gives the best-guess incantation to use for static inline functions. IfHAS_STATIC_INLINE is defined, this will give C99-style inline. IfHAS_STATIC_INLINE is not defined, this will give a plain 'static'. It will always be defined to something that gives static linkage. Possibilities include
static inline (c99)static __inline__ (gcc -ansi)static __inline (MSVC)static _inline (older MSVC)static (c89 compilers)PERL_THREAD_LOCALThis symbol, if defined, gives a linkage specification for thread-local storage. For example, for a C11 compiler this will be_Thread_local. Beware, some compilers are sensitive to the C language standard they are told to parse. For example, suncc defaults to C11, so our probe will report that_Thread_local can be used. However, if the -std=c99 is later added to the compiler flags, then_Thread_local will become a syntax error. Hence it is important for these flags to be consistent between probing and use.
U32_ALIGNMENT_REQUIREDThis symbol, if defined, indicates that you must access character data through U32-aligned pointers.
__ASSERT_This is a helper macro to avoid preprocessor issues, replaced by nothing unless under DEBUGGING, where it expands to an assert of its argument, followed by a comma (hence the comma operator). If we just used a straight assert(), we would get a comma with nothing before it when not DEBUGGING.
__ASSERT_(bool expr)ASSUMEASSUME is likeassert(), but it has a benefit in a release build. It is a hint to a compiler about a statement of fact in a function call free expression, which allows the compiler to generate better machine code. In a debug build,ASSUME(x) is a synonym forassert(x).ASSUME(0) means the control path is unreachable. In a for loop,ASSUME can be used to hint that a loop will run at least X times.ASSUME is based off MSVC's__assume intrinsic function, see its documents for more details.
ASSUME(bool expr)dNOOPDeclare nothing; typically used as a placeholder to replace something that used to declare something. Works on compilers that require declarations before any code.
dNOOP;END_EXTERN_CWhen not compiling using C++, expands to nothing. Otherwise ends a section of code already begun by a"START_EXTERN_C".
END_EXTERN_CEXTERN_CWhen not compiling using C++, expands to nothing. Otherwise is used in a declaration of a function to indicate the function should have external C linkage. This is required for things to work for just about all functions with external linkage compiled into perl. Often, you can use"START_EXTERN_C" ..."END_EXTERN_C" blocks surrounding all your code that you need to have this linkage.
Example usage:
EXTERN_C int flock(int fd, int op);LIKELYReturns the input unchanged, but at the same time it gives a branch prediction hint to the compiler that this condition is likely to be true.
LIKELY(bool expr)NOOPDo nothing; typically used as a placeholder to replace something that used to do something.
NOOP;PERL_UNUSED_ARGThis is used to suppress compiler warnings that a parameter to a function is not used. This situation can arise, for example, when a parameter is needed under some configuration conditions, but not others, so that C preprocessor conditional compilation causes it be used just sometimes.
PERL_UNUSED_ARG(void x);PERL_UNUSED_CONTEXTThis is used to suppress compiler warnings that the thread context parameter to a function is not used. This situation can arise, for example, when a C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_CONTEXT;PERL_UNUSED_DECLTells the compiler that the parameter in the function prototype just before it is not necessarily expected to be used in the function. Not that many compilers understand this, so this should only be used in cases where"PERL_UNUSED_ARG" can't conveniently be used.
Example usage:
Signal_tPerl_perly_sighandler(int sig, Siginfo_t *sip PERL_UNUSED_DECL, void *uap PERL_UNUSED_DECL, bool safe)PERL_UNUSED_RESULTThis macro indicates to discard the return value of the function call inside it,e.g.,
PERL_UNUSED_RESULT(foo(a, b))The main reason for this is that the combination ofgcc -Wunused-result (part of-Wall) and the__attribute__((warn_unused_result)) cannot be silenced with casting tovoid. This causes trouble when the system header files use the attribute.
UsePERL_UNUSED_RESULT sparingly, though, since usually the warning is there for a good reason: you might lose success/failure information, or leak resources, or changes in resources.
But sometimes you just want to ignore the return value,e.g., on codepaths soon ending up in abort, or in "best effort" attempts, or in situations where there is no good way to handle failures.
SometimesPERL_UNUSED_RESULT might not be the most natural way: another possibility is that you can capture the return value and use"PERL_UNUSED_VAR" on that.
PERL_UNUSED_RESULT(void x)PERL_UNUSED_VARThis is used to suppress compiler warnings that the variablex is not used. This situation can arise, for example, when a C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_VAR(void x);START_EXTERN_CWhen not compiling using C++, expands to nothing. Otherwise begins a section of code in which every function will effectively have"EXTERN_C" applied to it, that is to have external C linkage. The section is ended by a"END_EXTERN_C".
START_EXTERN_CSTMT_ENDSTMT_STARTThese allow a series of statements in a macro to be used as a single statement, as in
if (x) STMT_START { ... } STMT_END else ...Note that you can't return a value out of this construct and cannot use it as an operand to the comma operator. These limit its utility.
But, a value could be returned by constructing the API so that a pointer is passed and the macro dereferences this to set the return. If the value can be any of various types, depending on context, you can handle that situation in some situations by adding the type of the return as an extra accompanying parameter:
#define foo(param, type) STMT_START { type * param; *param = do_calc; ... } STMT_ENDThis could be awkward, so consider instead using a C languagestatic inline function.
If you do use this construct, it is easy to forget that it is a macro and not a function, and hence fall into traps that might not show up until someone someday writes code which contains names that clash with the ones you chose here, or calls it with a parameter which is an expression with side effects, the consequences of which you didn't think about. See"Writing safer macros" in perlhacktips for how to avoid these.
UNLIKELYReturns the input unchanged, but at the same time it gives a branch prediction hint to the compiler that this condition is likely to be false.
UNLIKELY(bool expr)BhkDISABLENOTE:BhkDISABLE isexperimental and may change or be removed without notice.
Temporarily disable an entry in this BHK structure, by clearing the appropriate flag.which is a preprocessor token indicating which entry to disable.
void BhkDISABLE(BHK *hk, token which)BhkENABLENOTE:BhkENABLE isexperimental and may change or be removed without notice.
Re-enable an entry in this BHK structure, by setting the appropriate flag.which is a preprocessor token indicating which entry to enable. This will assert (under -DDEBUGGING) if the entry doesn't contain a valid pointer.
void BhkENABLE(BHK *hk, token which)BhkENTRY_setNOTE:BhkENTRY_set isexperimental and may change or be removed without notice.
Set an entry in the BHK structure, and set the flags to indicate it is valid.which is a preprocessing token indicating which entry to set. The type ofptr depends on the entry.
void BhkENTRY_set(BHK *hk, token which, void *ptr)blockhook_registerNOTE:blockhook_register isexperimental and may change or be removed without notice.
Register a set of hooks to be called when the Perl lexical scope changes at compile time. See"Compile-time scope hooks" in perlguts.
NOTE:blockhook_register must be explicitly called asPerl_blockhook_register with anaTHX_ parameter.
void Perl_blockhook_register(pTHX_ BHK *hk)CPERLscopeDEPRECATED! It is planned to removeCPERLscope from a future release of Perl. Do not use it for new code; remove it from existing code.
Now a no-op.
void CPERLscope(void x)dTHXaOn threaded perls, setpTHX toa; on unthreaded perls, do nothing
dVARThis is now a synonym for dNOOP: declare nothing
GETENV_PRESERVES_OTHER_THREADThis symbol, if defined, indicates that the getenv system call doesn't zap the static buffer ofgetenv() in a different thread. The typicalgetenv() implementation will return a pointer to the proper position in **environ. But some may instead copy them to a static buffer ingetenv(). If there is a per-thread instance of that buffer, or the return points to **environ, then a many-reader/1-writer mutex will work; otherwise an exclusive locking mutex is required to prevent races.
HAS_PTHREAD_ATFORKThis symbol, if defined, indicates that thepthread_atfork routine is available to setup fork handlers.
HAS_PTHREAD_ATTR_SETSCOPEThis symbol, if defined, indicates that thepthread_attr_setscope system call is available to set the contention scope attribute of a thread attribute object.
HAS_PTHREAD_YIELDThis symbol, if defined, indicates that thepthread_yield routine is available to yield the execution of the current thread.sched_yield is preferable topthread_yield.
HAS_SCHED_YIELDThis symbol, if defined, indicates that thesched_yield routine is available to yield the execution of the current thread.sched_yield is preferable topthread_yield.
I_MACH_CTHREADSThis symbol, if defined, indicates to the C program that it should includemach/cthreads.h.
#ifdef I_MACH_CTHREADS #include <mach_cthreads.h>#endifI_PTHREADThis symbol, if defined, indicates to the C program that it should includepthread.h.
#ifdef I_PTHREAD #include <pthread.h>#endifMULTIPLICITYThis symbol, if defined, indicates that Perl should be built to use multiplicity.
OLD_PTHREAD_CREATE_JOINABLEThis symbol, if defined, indicates how to create pthread in joinable (aka undetached) state.NOTE: not defined ifpthread.h already has definedPTHREAD_CREATE_JOINABLE (the new version of the constant). If defined, known values arePTHREAD_CREATE_UNDETACHED and__UNDETACHED.
OLD_PTHREADS_APIThis symbol, if defined, indicates that Perl should be built to use the old draftPOSIX threadsAPI.
SCHED_YIELDThis symbol defines the way to yield the execution of the current thread. Known ways aresched_yield,pthread_yield, andpthread_yield withNULL.
cop_fetch_labelNOTE:cop_fetch_label isexperimental and may change or be removed without notice.
Returns the label attached to a cop, and stores its length in bytes into*len. Upon return,*flags will be set to eitherSVf_UTF8 or 0.
Alternatively, use the macro"CopLABEL_len_flags"; or if you don't need to know if the label is UTF-8 or not, the macro"CopLABEL_len"; or if you additionally don't need to know the length,"CopLABEL".
const char * cop_fetch_label(COP * const cop, STRLEN *len, U32 *flags)CopFILEReturns the name of the file associated with theCOPc
const char * CopFILE(const COP * c)CopFILEAVReturns the AV associated with theCOPc, creating it if necessary.
AV * CopFILEAV(const COP * c)CopFILEAVnReturns the AV associated with theCOPc, returning NULL if it doesn't already exist.
AV * CopFILEAVn(const COP * c)CopFILE_copyEfficiently copies the cop file name from one COP to another. Wraps the required logic to do a refcounted copy under threads or not.
void CopFILE_copy(COP * dst, COP * src)CopFILE_freeFrees the file data in a cop. Under the hood this is a refcounting operation.
void CopFILE_free(COP * c)CopFILEGVReturns the GV associated with theCOPc
GV * CopFILEGV(const COP * c)CopFILEGV_setAvailable only on unthreaded perls. Makespv the name of the file associated with theCOPc
void CopFILEGV_set(COP *c, GV *gv)CopFILE_LENReturns the length of the file associated with theCOPc
const char * CopFILE_LEN(const COP * c)CopFILE_setMakespv the name of the file associated with theCOPc
void CopFILE_set(COP * c, const char * pv)CopFILE_setnMakespv the name of the file associated with theCOPc
void CopFILE_setn(COP * c, const char * pv, STRLEN len)CopFILESVReturns the SV associated with theCOPc
SV * CopFILESV(const COP * c)cophh_copyNOTE:cophh_copy isexperimental and may change or be removed without notice.
Make and return a complete copy of the cop hints hashcophh.
COPHH * cophh_copy(COPHH *cophh)cophh_delete_pvcophh_delete_pvncophh_delete_pvscophh_delete_svNOTE: all these forms areexperimental and may change or be removed without notice.
These delete a key and its associated value from the cop hints hashcophh, and return the modified hash. The returned hash pointer is in general not the same as the hash pointer that was passed in. The input hash is consumed by the function, and the pointer to it must not be subsequently used. Use"cophh_copy" if you need both hashes.
The forms differ in how the key is specified. In all forms, the key is pointed to bykey. In the plainpv form, the key is a C language NUL-terminated string. In thepvs form, the key is a C language string literal. In thepvn form, an additional parameter,keylen, specifies the length of the string, which hence, may contain embedded-NUL characters. In thesv form,*key is an SV, and the key is the PV extracted from that. using"SvPV_const".
hash is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from thepvs form, as it is computed automatically at compile time.
The only flag currently used from theflags parameter isCOPHH_KEY_UTF8. It is illegal to set this in thesv form. In thepv* forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). Thesv form uses the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_delete_pv (COPHH *cophh, const char *key, U32 hash, U32 flags)COPHH * cophh_delete_pvn(COPHH *cophh, const char *key, STRLEN keylen, U32 hash, U32 flags)COPHH * cophh_delete_pvs(COPHH *cophh, "key", U32 flags)COPHH * cophh_delete_sv (COPHH *cophh, SV *key, U32 hash, U32 flags)cophh_exists_pvnNOTE:cophh_exists_pvn isexperimental and may change or be removed without notice.
These look up the hint entry in the copcop with the key specified bykey (andkeylen in thepvn form), returning true if a value exists, and false otherwise.
The forms differ in how the key is specified. In the plainpv form, the key is a C language NUL-terminated string. In thepvs form, the key is a C language string literal. In thepvn form, an additional parameter,keylen, specifies the length of the string, which hence, may contain embedded-NUL characters. In thesv form,*key is an SV, and the key is the PV extracted from that. using"SvPV_const".
hash is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from thepvs form, as it is computed automatically at compile time.
The only flag currently used from theflags parameter isCOPHH_KEY_UTF8. It is illegal to set this in thesv form. In thepv* forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). Thesv form uses the underlying SV to determine the UTF-8ness of the octets.
bool cophh_exists_pvn(const COPHH *cophh, const char *key, STRLEN keylen, U32 hash, U32 flags)cophh_fetch_pvcophh_fetch_pvncophh_fetch_pvscophh_fetch_svNOTE: all these forms areexperimental and may change or be removed without notice.
These look up the entry in the cop hints hashcophh with the key specified bykey (andkeylen in thepvn form), returning that value as a mortal scalar copy, or&PL_sv_placeholder if there is no value associated with the key.
The forms differ in how the key is specified. In the plainpv form, the key is a C language NUL-terminated string. In thepvs form, the key is a C language string literal. In thepvn form, an additional parameter,keylen, specifies the length of the string, which hence, may contain embedded-NUL characters. In thesv form,*key is an SV, and the key is the PV extracted from that. using"SvPV_const".
hash is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from thepvs form, as it is computed automatically at compile time.
The only flag currently used from theflags parameter isCOPHH_KEY_UTF8. It is illegal to set this in thesv form. In thepv* forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). Thesv form uses the underlying SV to determine the UTF-8ness of the octets.
SV * cophh_fetch_pv (const COPHH *cophh, const char *key, U32 hash, U32 flags)SV * cophh_fetch_pvn(const COPHH *cophh, const char *key, STRLEN keylen, U32 hash, U32 flags)SV * cophh_fetch_pvs(const COPHH *cophh, "key", U32 flags)SV * cophh_fetch_sv (const COPHH *cophh, SV *key, U32 hash, U32 flags)cophh_freeNOTE:cophh_free isexperimental and may change or be removed without notice.
Discard the cop hints hashcophh, freeing all resources associated with it.
void cophh_free(COPHH *cophh)cophh_2hvNOTE:cophh_2hv isexperimental and may change or be removed without notice.
Generates and returns a standard Perl hash representing the full set of key/value pairs in the cop hints hashcophh.flags is currently unused and must be zero.
HV * cophh_2hv(const COPHH *cophh, U32 flags)cophh_new_emptyNOTE:cophh_new_empty isexperimental and may change or be removed without notice.
Generate and return a fresh cop hints hash containing no entries.
COPHH * cophh_new_empty()cophh_store_pvcophh_store_pvncophh_store_pvscophh_store_svNOTE: all these forms areexperimental and may change or be removed without notice.
These store a value, associated with a key, in the cop hints hashcophh, and return the modified hash. The returned hash pointer is in general not the same as the hash pointer that was passed in. The input hash is consumed by the function, and the pointer to it must not be subsequently used. Use"cophh_copy" if you need both hashes.
value is the scalar value to store for this key.value is copied by these functions, which thus do not take ownership of any reference to it, and hence later changes to the scalar will not be reflected in the value visible in the cop hints hash. Complex types of scalar will not be stored with referential integrity, but will be coerced to strings.
The forms differ in how the key is specified. In all forms, the key is pointed to bykey. In the plainpv form, the key is a C language NUL-terminated string. In thepvs form, the key is a C language string literal. In thepvn form, an additional parameter,keylen, specifies the length of the string, which hence, may contain embedded-NUL characters. In thesv form,*key is an SV, and the key is the PV extracted from that. using"SvPV_const".
hash is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from thepvs form, as it is computed automatically at compile time.
The only flag currently used from theflags parameter isCOPHH_KEY_UTF8. It is illegal to set this in thesv form. In thepv* forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). Thesv form uses the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_store_pv (COPHH *cophh, const char *key, U32 hash, SV *value, U32 flags)COPHH * cophh_store_pvn(COPHH *cophh, const char *key, STRLEN keylen, U32 hash, SV *value, U32 flags)COPHH * cophh_store_pvs(COPHH *cophh, "key", SV *value, U32 flags)COPHH * cophh_store_sv (COPHH *cophh, SV *key, U32 hash, SV *value, U32 flags)cop_hints_exists_pvcop_hints_exists_pvncop_hints_exists_pvscop_hints_exists_svThese look up the hint entry in the copcop with the key specified bykey (andkeylen in thepvn form), returning true if a value exists, and false otherwise.
The forms differ in how the key is specified. In all forms, the key is pointed to bykey. In the plainpv form, the key is a C language NUL-terminated string. In thepvs form, the key is a C language string literal. In thepvn form, an additional parameter,keylen, specifies the length of the string, which hence, may contain embedded-NUL characters. In thesv form,*key is an SV, and the key is the PV extracted from that. using"SvPV_const".
hash is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from thepvs form, as it is computed automatically at compile time.
The only flag currently used from theflags parameter isCOPHH_KEY_UTF8. It is illegal to set this in thesv form. In thepv* forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). Thesv form uses the underlying SV to determine the UTF-8ness of the octets.
bool cop_hints_exists_pv (const COP *cop, const char *key, U32 hash, U32 flags)bool cop_hints_exists_pvn(const COP *cop, const char *key, STRLEN keylen, U32 hash, U32 flags)bool cop_hints_exists_pvs(const COP *cop, "key", U32 flags)bool cop_hints_exists_sv (const COP *cop, SV *key, U32 hash, U32 flags)cop_hints_fetch_pvcop_hints_fetch_pvncop_hints_fetch_pvscop_hints_fetch_svThese look up the hint entry in the copcop with the key specified bykey (andkeylen in thepvn form), returning that value as a mortal scalar copy, or&PL_sv_placeholder if there is no value associated with the key.
The forms differ in how the key is specified. In the plainpv form, the key is a C language NUL-terminated string. In thepvs form, the key is a C language string literal. In thepvn form, an additional parameter,keylen, specifies the length of the string, which hence, may contain embedded-NUL characters. In thesv form,*key is an SV, and the key is the PV extracted from that. using"SvPV_const".
hash is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from thepvs form, as it is computed automatically at compile time.
The only flag currently used from theflags parameter isCOPHH_KEY_UTF8. It is illegal to set this in thesv form. In thepv* forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). Thesv form uses the underlying SV to determine the UTF-8ness of the octets.
SV * cop_hints_fetch_pv (const COP *cop, const char *key, U32 hash, U32 flags)SV * cop_hints_fetch_pvn(const COP *cop, const char *key, STRLEN keylen, U32 hash, U32 flags)SV * cop_hints_fetch_pvs(const COP *cop, "key", U32 flags)SV * cop_hints_fetch_sv (const COP *cop, SV *key, U32 hash, U32 flags)cop_hints_2hvGenerates and returns a standard Perl hash representing the full set of hint entries in the copcop.flags is currently unused and must be zero.
HV * cop_hints_2hv(const COP *cop, U32 flags)CopLABELCopLABEL_lenCopLABEL_len_flagsThese return the label attached to a cop.
CopLABEL_len andCopLABEL_len_flags additionally store the number of bytes comprising the returned label into*len.
CopLABEL_len_flags additionally returns the UTF-8ness of the returned label, by setting*flags to 0 orSVf_UTF8.
const char * CopLABEL (COP *const cop)const char * CopLABEL_len (COP *const cop, STRLEN *len)const char * CopLABEL_len_flags(COP *const cop, STRLEN *len, U32 *flags)CopLINEReturns the line number in the source code associated with theCOPc
line_t CopLINE(const COP * c)CopSTASHReturns the stash associated withc.
HV * CopSTASH(const COP * c)CopSTASH_eqReturns a boolean as to whether or nothv is the stash associated withc.
bool CopSTASH_eq(const COP * c, const HV * hv)CopSTASHPVReturns the package name of the stash associated withc, orNULL if no associated stash
char * CopSTASHPV(const COP * c)CopSTASHPV_setSet the package name of the stash associated withc, to the NUL-terminated C stringp, creating the package if necessary.
void CopSTASHPV_set(COP * c, const char * pv)CopSTASH_setSet the stash associated withc tohv.
bool CopSTASH_set(COP * c, HV * hv)cop_store_labelNOTE:cop_store_label isexperimental and may change or be removed without notice.
Save a label into acop_hints_hash. You need to set flags toSVf_UTF8 for a UTF-8 label. Any other flag is ignored.
void cop_store_label(COP * const cop, const char *label, STRLEN len, U32 flags)PERL_SIUse this typedef to declare variables that are to holdstruct stackinfo.
PL_curcopThe currently active COP (control op) roughly representing the current statement in the source.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
COP* PL_curcopRCPV_LENReturns the length of a pv created withrcpv_new(). Note that this reflects the length of the string from the callers point of view, it does not include the mandatory null which is always injected at the end of the string by rcpv_new(). No checks are performed to ensure thatpv was actually allocated withrcpv_new(), it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_LEN(char *pv)RCPV_REFCNT_decDecrements the refcount for achar * pointer which was created with a call torcpv_new(). Same as calling rcpv_free(). No checks are performed to ensure thatpv was actually allocated withrcpv_new(), it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_REFCNT_dec(char *pv)RCPV_REFCNT_incIncrements the refcount for achar * pointer which was created with a call torcpv_new(). Same as calling rcpv_copy(). No checks are performed to ensure thatpv was actually allocated withrcpv_new(), it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_REFCNT_inc(char *pv)RCPV_REFCOUNTReturns the refcount for a pv created withrcpv_new(). No checks are performed to ensure thatpv was actually allocated withrcpv_new(), it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_REFCOUNT(char *pv)RCPVxReturns the RCPV structure (struct rcpv) for a refcounted string pv created withrcpv_new(). No checks are performed to ensure thatpv was actually allocated withrcpv_new(), it is the callers responsibility to ensure that this is the case.
RCPV * RCPVx(char *pv)custom_op_registerRegister a custom op. See"Custom Operators" in perlguts.
NOTE:custom_op_register must be explicitly called asPerl_custom_op_register with anaTHX_ parameter.
void Perl_custom_op_register(pTHX_ Perl_ppaddr_t ppaddr, const XOP *xop)Perl_custom_op_xopReturn the XOP structure for a given custom op. This macro should be considered internal toOP_NAME and the other access macros: use them instead. This macro does call a function. Prior to 5.19.6, this was implemented as a function.
const XOP * Perl_custom_op_xop(pTHX_ const OP *o)XopDISABLETemporarily disable a member of the XOP, by clearing the appropriate flag.
void XopDISABLE(XOP *xop, token which)XopENABLEReenable a member of the XOP which has been disabled.
void XopENABLE(XOP *xop, token which)XopENTRYReturn a member of the XOP structure.which is a cpp token indicating which entry to return. If the member is not set this will return a default value. The return type depends onwhich. This macro evaluates its arguments more than once. If you are usingPerl_custom_op_xop to retrieve aXOP * from aOP *, use the more efficient"XopENTRYCUSTOM" instead.
XopENTRY(XOP *xop, token which)XopENTRYCUSTOMExactly likeXopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which) but more efficient. Thewhich parameter is identical to"XopENTRY".
XopENTRYCUSTOM(const OP *o, token which)XopENTRY_setSet a member of the XOP structure.which is a cpp token indicating which entry to set. See"Custom Operators" in perlguts for details about the available members and how they are used. This macro evaluates its argument more than once.
void XopENTRY_set(XOP *xop, token which, value)XopFLAGSReturn the XOP's flags.
U32 XopFLAGS(XOP *xop)This section documents functions to manipulate CVs which are code-values, meaning subroutines. For more information, seeperlguts.
caller_cxThe XSUB-writer's equivalent ofcaller(). The returnedPERL_CONTEXT structure can be interrogated to find all the information returned to Perl bycaller. Note that XSUBs don't get a stack frame, socaller_cx(0, NULL) will return information for the immediately-surrounding Perl code.
This function skips over the automatic calls to&DB::sub made on the behalf of the debugger. If the stack frame requested was a sub called byDB::sub, the return value will be the frame for the call toDB::sub, since that has the correct line number/etc. for the call site. Ifdbcxp is non-NULL, it will be set to a pointer to the frame for the sub call itself.
const PERL_CONTEXT * caller_cx(I32 level, const PERL_CONTEXT **dbcxp)CvDEPTHReturns the recursion level of the CVsv. Hence >= 2 indicates we are in a recursive call.
I32 * CvDEPTH(const CV * const sv)CvGVReturns the GV associated with the CVsv, reifying it if necessary.
GV * CvGV(CV *sv)CvSTASHReturns the stash of the CV. A stash is the symbol table hash, containing the package-scoped variables in the package where the subroutine was defined. For more information, seeperlguts.
This also has a special use with XS AUTOLOAD subs. See"Autoloading with XSUBs" in perlguts.
HV* CvSTASH(CV* cv)find_runcvLocate the CV corresponding to the currently executing sub or eval. Ifdb_seqp is non_null, skip CVs that are in the DB package and populate*db_seqp with the cop sequence number at the point that the DB:: code was entered. (This allows debuggers to eval in the scope of the breakpoint rather than in the scope of the debugger itself.)
CV * find_runcv(U32 *db_seqp)get_cvget_cvn_flagsget_cvsThese return the CV of the specified Perl subroutine.flags are passed togv_fetchpvn_flags. IfGV_ADD is set and the Perl subroutine does not exist then it will be declared (which has the same effect as sayingsub name;). IfGV_ADD is not set and the subroutine does not exist, then NULL is returned.
The forms differ only in how the subroutine is specified.. Withget_cvs, the name is a literal C string, enclosed in double quotes. Withget_cv, the name is given by thename parameter, which must be a NUL-terminated C string. Withget_cvn_flags, the name is also given by thename parameter, but it is a Perl string (possibly containing embedded NUL bytes), and its length in bytes is contained in thelen parameter.
NOTE: theperl_get_cv() form isdeprecated.
NOTE: theperl_get_cvn_flags() form isdeprecated.
NOTE: theperl_get_cvs() form isdeprecated.
CV * get_cv (const char *name, I32 flags)CV * get_cvn_flags(const char *name, STRLEN len, I32 flags)CV * get_cvs ("string", I32 flags)NullcvDEPRECATED! It is planned to removeNullcv from a future release of Perl. Do not use it for new code; remove it from existing code.
Null CV pointer.
(deprecated - use(CV *)NULL instead)
av_dumpDumps the contents of an AV to theSTDERR filehandle, Similar to using Devel::Peek on an arrayref but does not expect an RV wrapper. Dumps contents to a depth of 3 levels deep.
void av_dump(AV *av)debdeb_nocontextWhen perl is compiled with-DDEBUGGING, this prints to STDERR the information given by the arguments, prefaced by the name of the file containing the script causing the call, and the line number within that file.
If thev (verbose) debugging option is in effect, the process id is also printed.
The two forms differ only in thatdeb_nocontext does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE:deb must be explicitly called asPerl_deb with anaTHX_ parameter.
void Perl_deb (pTHX_ const char *pat, ...)void deb_nocontext(const char *pat, ...)debstackDump the current stack
I32 debstack()dump_allDumps the entire optree of the current program starting atPL_main_root toSTDERR. Also dumps the optrees for all visible subroutines inPL_defstash.
void dump_all()dump_c_backtraceDumps the C backtrace to the givenfp.
Returns true if a backtrace could be retrieved, false if not.
bool dump_c_backtrace(PerlIO *fp, int max_depth, int skip)dump_formDumps the contents of the format contained in the GVgv toSTDERR, or a message that one doesn't exist.
void dump_form(const GV *gv)dump_packsubsDumps the optrees for all visible subroutines instash.
void dump_packsubs(const HV *stash)get_c_backtrace_dumpReturns a SV containing a dump ofdepth frames of the call stack, skipping theskip innermost ones.depth of 20 is usually enough.
The appended output looks like:
...1 10e004812:0082 Perl_croak util.c:1716 /usr/bin/perl2 10df8d6d2:1d72 perl_parse perl.c:3975 /usr/bin/perl...The fields are tab-separated. The first column is the depth (zero being the innermost non-skipped frame). In the hex:offset, the hex is where the program counter was inS_parse_body, and the :offset (might be missing) tells how much inside theS_parse_body the program counter was.
Theutil.c:1716 is the source code file and line number.
The/usr/bin/perl is obvious (hopefully).
Unknowns are"-". Unknowns can happen unfortunately quite easily: if the platform doesn't support retrieving the information; if the binary is missing the debug information; if the optimizer has transformed the code by for example inlining.
SV * get_c_backtrace_dump(int max_depth, int skip)gv_dumpDump the name and, if they differ, the effective name of the GVgv toSTDERR.
void gv_dump(GV *gv)HAS_BACKTRACEThis symbol, if defined, indicates that thebacktrace() routine is available to get a stack trace. Theexecinfo.h header must be included to use this routine.
hv_dumpDumps the contents of an HV to theSTDERR filehandle. Similar to using Devel::Peek on an hashref but does not expect an RV wrapper. Dumps contents to a depth of 3 levels deep.
void hv_dump(HV *hv)magic_dumpDumps the contents of the MAGICmg toSTDERR.
void magic_dump(const MAGIC *mg)op_classGiven an op, determine what type of struct it has been allocated as. Returns one of the OPclass enums, such as OPclass_LISTOP.
OPclass op_class(const OP *o)op_dumpDumps the optree starting at OPo toSTDERR.
void op_dump(const OP *o)PL_opDescribed inperlhacktips.
PL_sv_serialDescribed inperlhacktips.
pmop_dumpDump an OP that is related to Pattern Matching, such ass/foo/bar/; these require special handling.
void pmop_dump(PMOP *pm)sv_dumpDumps the contents of an SV to theSTDERR filehandle.
For an example of its output, seeDevel::Peek. If the item is an SvROK it will dump items to a depth of 4, otherwise it will dump only the top level item, which means that it will not dump the contents of an AV * or HV *. For that useav_dump() orhv_dump().
void sv_dump(SV *sv)sv_dump_depthDumps the contents of an SV to theSTDERR filehandle to the depth requested. This function can be used on any SV derived type (GV, HV, AV) with an appropriate cast. This is a more flexible variant of sv_dump(). For example
HV *hv = ...;sv_dump_depth((SV*)hv, 2);would dump the hv, its keys and values, but would not recurse into any RV values.
void sv_dump_depth(SV *sv, I32 depth)vdebThis is like"deb", butargs are an encapsulated argument list.
void vdeb(const char *pat, va_list *args)formform_nocontextThese take a sprintf-style format pattern and conventional (non-SV) arguments and return the formatted string.
(char *) Perl_form(pTHX_ const char* pat, ...)can be used any place a string (char *) is required:
char * s = Perl_form("%d.%d",major,minor);They use a single (per-thread) private buffer so if you want to format several strings you must explicitly copy the earlier strings away (and free the copies when you are done).
The two forms differ only in thatform_nocontext does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE:form must be explicitly called asPerl_form with anaTHX_ parameter.
char * Perl_form (pTHX_ const char *pat, ...)char * form_nocontext(const char *pat, ...)messmess_nocontextThese take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
Normally, the resulting message is returned in a new mortal SV. But during global destruction a single SV may be shared between uses of this function.
The two forms differ only in thatmess_nocontext does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE:mess must be explicitly called asPerl_mess with anaTHX_ parameter.
SV * Perl_mess (pTHX_ const char *pat, ...)SV * mess_nocontext(const char *pat, ...)mess_svExpands a message, intended for the user, to include an indication of the current location in the code, if the message does not already appear to be complete.
basemsg is the initial message or object. If it is a reference, it will be used as-is and will be the result of this function. Otherwise it is used as a string, and if it already ends with a newline, it is taken to be complete, and the result of this function will be the same string. If the message does not end with a newline, then a segment such asat foo.pl line 37 will be appended, and possibly other clauses indicating the current state of execution. The resulting message will end with a dot and a newline.
Normally, the resulting message is returned in a new mortal SV. During global destruction a single SV may be shared between uses of this function. Ifconsume is true, then the function is permitted (but not required) to modify and returnbasemsg instead of allocating a new SV.
SV * mess_sv(SV *basemsg, bool consume)pv_displaySimilar to
pv_escape(dsv,pv,cur,pvlim,PERL_PV_ESCAPE_QUOTE);except that an additional "\0" will be appended to the string when len > cur and pv[cur] is "\0".
Note that the final string may be up to 7 chars longer than pvlim.
char * pv_display(SV *dsv, const char *pv, STRLEN cur, STRLEN len, STRLEN pvlim)pv_escapeEscapes at most the firstcount chars ofpv and puts the results intodsv such that the size of the escaped string will not exceedmax chars and will not contain any incomplete escape sequences. The number of bytes escaped will be returned in theSTRLEN *escaped parameter if it is not null. When thedsv parameter is null no escaping actually occurs, but the number of bytes that would be escaped were it not null will be calculated.
If flags containsPERL_PV_ESCAPE_QUOTE then any double quotes in the string will also be escaped.
Normally the SV will be cleared before the escaped string is prepared, but whenPERL_PV_ESCAPE_NOCLEAR is set this will not occur.
IfPERL_PV_ESCAPE_UNI is set then the input string is treated as UTF-8. IfPERL_PV_ESCAPE_UNI_DETECT is set then the input string is scanned usingis_utf8_string() to determine if it is UTF-8.
IfPERL_PV_ESCAPE_ALL is set then all input chars will be output using\x01F1 style escapes, otherwise ifPERL_PV_ESCAPE_NONASCII is set, only non-ASCII chars will be escaped using this style; otherwise, only chars above 255 will be so escaped; other non printable chars will use octal or common escaped patterns like\n. Otherwise, ifPERL_PV_ESCAPE_NOBACKSLASH then all chars below 255 will be treated as printable and will be output as literals. ThePERL_PV_ESCAPE_NON_WC modifies the previous rules to cause word chars, unicode or otherwise, to be output as literals, note this uses the *unicode* rules for deciding on word characters.
IfPERL_PV_ESCAPE_FIRSTCHAR is set then only the first char of the string will be escaped, regardless of max. If the output is to be in hex, then it will be returned as a plain hex sequence. Thus the output will either be a single char, an octal escape sequence, a special escape like\n or a hex value.
IfPERL_PV_ESCAPE_RE is set then the escape char used will be a"%" and not a"\\". This is because regexes very often contain backslashed sequences, whereas"%" is not a particularly common character in patterns.
Returns a pointer to the escaped text as held bydsv.
char * pv_escape(SV *dsv, char const * const str, const STRLEN count, STRLEN max, STRLEN * const escaped, U32 flags)pv_prettyConverts a string into something presentable, handling escaping viapv_escape() and supporting quoting and ellipses.
If thePERL_PV_PRETTY_QUOTE flag is set then the result will be double quoted with any double quotes in the string escaped. Otherwise if thePERL_PV_PRETTY_LTGT flag is set then the result be wrapped in angle brackets.
If thePERL_PV_PRETTY_ELLIPSES flag is set and not all characters in string were output then an ellipsis... will be appended to the string. Note that this happens AFTER it has been quoted.
Ifstart_color is non-null then it will be inserted after the opening quote (if there is one) but before the escaped text. Ifend_color is non-null then it will be inserted after the escaped text but before any quotes or ellipses.
Returns a pointer to the prettified text as held bydsv.
char * pv_pretty(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, char const * const start_color, char const * const end_color, const U32 flags)vformLike"form" but but the arguments are an encapsulated argument list.
char * vform(const char *pat, va_list *args)vmesspat andargs are a sprintf-style format pattern and encapsulated argument list, respectively. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
Normally, the resulting message is returned in a new mortal SV. During global destruction a single SV may be shared between uses of this function.
SV * vmess(const char *pat, va_list *args)call_atexitAdd a functionfn to the list of functions to be called at global destruction.ptr will be passed as an argument tofn; it can point to astruct so that you can pass anything you want.
Note that under threads,fn may run multiple times. This is because the list is executed each time the current or any descendent thread terminates.
void call_atexit(ATEXIT_t fn, void *ptr)cv_cloneClone a CV, making a lexical closure.proto supplies the prototype of the function: its code, pad structure, and other attributes. The prototype is combined with a capture of outer lexicals to which the code refers, which are taken from the currently-executing instance of the immediately surrounding code.
CV * cv_clone(CV *proto)cv_nameReturns an SV containing the name of the CV, mainly for use in error reporting. The CV may actually be a GV instead, in which case the returned SV holds the GV's name. Anything other than a GV or CV is treated as a string already holding the sub name, but this could change in the future.
An SV may be passed as a second argument. If so, the name will be assigned to it and it will be returned. Otherwise the returned SV will be a new mortal.
Ifflags has theCV_NAME_NOTQUAL bit set, then the package name will not be included. If the first argument is neither a CV nor a GV, this flag is ignored (subject to change).
SV * cv_name(CV *cv, SV *sv, U32 flags)cv_undefClear out all the active components of a CV. This can happen either by an explicitundef &foo, or by the reference count going to zero. In the former case, we keep theCvOUTSIDE pointer, so that any anonymous children can still follow the full lexical scope chain.
void cv_undef(CV *cv)find_rundefsvReturns the global variable$_.
SV * find_rundefsv()get_op_descsDEPRECATED! It is planned to removeget_op_descs from a future release of Perl. Do not use it for new code; remove it from existing code.
Return a pointer to the array of all the descriptions of the various OPs Given an opcode from the enum inopcodes.h,PL_op_desc[opcode] returns a pointer to a C language string giving its description.
char ** get_op_descs()get_op_namesDEPRECATED! It is planned to removeget_op_names from a future release of Perl. Do not use it for new code; remove it from existing code.
Return a pointer to the array of all the names of the various OPs Given an opcode from the enum inopcodes.h,PL_op_name[opcode] returns a pointer to a C language string giving its name.
char ** get_op_names()intro_my"Introduce"my variables to visible status. This is called during parsing at the end of each statement to make lexical variables visible to subsequent statements.
U32 intro_my()load_moduleload_module_nocontextThese load the module whose name is pointed to by the string part ofname. Note that the actual module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". ver, if specified and not NULL, provides version semantics similar touse Foo::Bar VERSION. The optional trailing arguments can be used to specify arguments to the module'simport() method, similar touse Foo::Bar VERSION LIST; their precise handling depends on the flags. The flags argument is a bitwise-ORed collection of any ofPERL_LOADMOD_DENY,PERL_LOADMOD_NOIMPORT, orPERL_LOADMOD_IMPORT_OPS (or 0 for no flags).
IfPERL_LOADMOD_NOIMPORT is set, the module is loaded as if with an empty import list, as inuse Foo::Bar (); this is the only circumstance in which the trailing optional arguments may be omitted entirely. Otherwise, ifPERL_LOADMOD_IMPORT_OPS is set, the trailing arguments must consist of exactly oneOP*, containing the op tree that produces the relevant import arguments. Otherwise, the trailing arguments must all beSV* values that will be used as import arguments; and the list must be terminated with(SV*) NULL. If neitherPERL_LOADMOD_NOIMPORT norPERL_LOADMOD_IMPORT_OPS is set, the trailingNULL pointer is needed even if no import arguments are desired. The reference count for each specifiedSV* argument is decremented. In addition, thename argument is modified.
IfPERL_LOADMOD_DENY is set, the module is loaded as if withno rather thanuse.
load_module andload_module_nocontext have the same apparent signature, but the former hides the fact that it is accessing a thread context parameter. So use the latter when you get a compilation error aboutpTHX.
void load_module (U32 flags, SV *name, SV *ver, ...)void load_module_nocontext(U32 flags, SV *name, SV *ver, ...)my_exitA wrapper for the C libraryexit(3), honoring what"PL_exit_flags" in perlapi say to do.
void my_exit(U32 status)my_failure_exitExit the running Perl process with an error.
On non-VMS platforms, this is essentially equivalent to"my_exit", usingerrno, but forces an en error code of 255 iferrno is 0.
On VMS, it takes care to set the appropriate severity bits in the exit status.
void my_failure_exit()my_strlcatThe C librarystrlcat if available, or a Perl implementation of it. This operates on CNUL-terminated strings.
my_strlcat() appends stringsrc to the end ofdst. It will append at mostsize - strlen(dst) - 1 bytes. It will thenNUL-terminate, unlesssize is 0 or the originaldst string was longer thansize (in practice this should not happen as it means that eithersize is incorrect or thatdst is not a properNUL-terminated string).
Note thatsize is the full size of the destination buffer and the result is guaranteed to beNUL-terminated if there is room. Note that room for theNUL should be included insize.
The return value is the total length thatdst would have ifsize is sufficiently large. Thus it is the initial length ofdst plus the length ofsrc. Ifsize is smaller than the return, the excess was not appended.
Size_t my_strlcat(char *dst, const char *src, Size_t size)my_strlcpyThe C librarystrlcpy if available, or a Perl implementation of it. This operates on CNUL-terminated strings.
my_strlcpy() copies up tosize - 1 bytes from the stringsrc todst,NUL-terminating the result ifsize is not 0.
The return value is the total lengthsrc would be if the copy completely succeeded. If it is larger thansize, the excess was not copied.
Size_t my_strlcpy(char *dst, const char *src, Size_t size)newPADNAMELISTNOTE:newPADNAMELIST isexperimental and may change or be removed without notice.
Creates a new pad name list.max is the highest index for which space is allocated.
PADNAMELIST * newPADNAMELIST(size_t max)newPADNAMEouterNOTE:newPADNAMEouter isexperimental and may change or be removed without notice.
Constructs and returns a new pad name. Only use this function for names that refer to outer lexicals. (See also"newPADNAMEpvn".)outer is the outer pad name that this one mirrors. The returned pad name has thePADNAMEf_OUTER flag already set.
PADNAME * newPADNAMEouter(PADNAME *outer)newPADNAMEpvnNOTE:newPADNAMEpvn isexperimental and may change or be removed without notice.
Constructs and returns a new pad name.s must be a UTF-8 string. Do not use this for pad names that point to outer lexicals. See"newPADNAMEouter".
PADNAME * newPADNAMEpvn(const char *s, STRLEN len)nothreadhookStub that provides thread hook for perl_destruct when there are no threads.
int nothreadhook()pad_add_anonAllocates a place in the currently-compiling pad (via"pad_alloc") for an anonymous function that is lexically scoped inside the currently-compiling function. The functionfunc is linked into the pad, and itsCvOUTSIDE link to the outer scope is weakened to avoid a reference loop.
One reference count is stolen, so you may need to doSvREFCNT_inc(func).
optype should be an opcode indicating the type of operation that the pad entry is to support. This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_add_anon(CV *func, I32 optype)pad_add_name_pvExactly like"pad_add_name_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_add_name_pv(const char *name, const U32 flags, HV *typestash, HV *ourstash)pad_add_name_pvnAllocates a place in the currently-compiling pad for a named lexical variable. Stores the name and other metadata in the name part of the pad, and makes preparations to manage the variable's lexical scoping. Returns the offset of the allocated pad slot.
namepv/namelen specify the variable's name in UTF-8, including leading sigil. Iftypestash is non-null, the name is for a typed lexical, and this identifies the type. Ifourstash is non-null, it's a lexical reference to a package variable, and this identifies the package. The following flags can be OR'ed together:
padadd_OUR redundantly specifies if it's a package varpadadd_STATE variable will retain value persistentlypadadd_NO_DUP_CHECK skip check for lexical shadowingpadadd_FIELD specifies that the lexical is a field for a classPADOFFSET pad_add_name_pvn(const char *namepv, STRLEN namelen, U32 flags, HV *typestash, HV *ourstash)pad_add_name_svExactly like"pad_add_name_pvn", but takes the name string in the form of an SV instead of a string/length pair.
PADOFFSET pad_add_name_sv(SV *name, U32 flags, HV *typestash, HV *ourstash)pad_allocNOTE:pad_alloc isexperimental and may change or be removed without notice.
Allocates a place in the currently-compiling pad, returning the offset of the allocated pad slot. No name is initially attached to the pad slot.tmptype is a set of flags indicating the kind of pad entry required, which will be set in the value SV for the allocated pad entry:
SVs_PADMY named lexical variable ("my", "our", "state")SVs_PADTMP unnamed temporary storeSVf_READONLY constant shared between recursion levelsSVf_READONLY has been supported here only since perl 5.20. To work with earlier versions as well, useSVf_READONLY|SVs_PADTMP.SVf_READONLY does not cause the SV in the pad slot to be marked read-only, but simply tellspad_alloc that itwill be made read-only (by the caller), or at least should be treated as such.
optype should be an opcode indicating the type of operation that the pad entry is to support. This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_alloc(I32 optype, U32 tmptype)pad_findmy_pvExactly like"pad_findmy_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_findmy_pv(const char *name, U32 flags)pad_findmy_pvnGiven the name of a lexical variable, find its position in the currently-compiling pad.namepv/namelen specify the variable's name, including leading sigil.flags is reserved and must be zero. If it is not in the current pad but appears in the pad of any lexically enclosing scope, then a pseudo-entry for it is added in the current pad. Returns the offset in the current pad, orNOT_IN_PAD if no such lexical is in scope.
PADOFFSET pad_findmy_pvn(const char *namepv, STRLEN namelen, U32 flags)pad_findmy_svExactly like"pad_findmy_pvn", but takes the name string in the form of an SV instead of a string/length pair.
PADOFFSET pad_findmy_sv(SV *name, U32 flags)padnamelist_fetchNOTE:padnamelist_fetch isexperimental and may change or be removed without notice.
Fetches the pad name from the given index.
PADNAME * padnamelist_fetch(PADNAMELIST *pnl, SSize_t key)padnamelist_storeNOTE:padnamelist_store isexperimental and may change or be removed without notice.
Stores the pad name (which may be null) at the given index, freeing any existing pad name in that slot.
PADNAME ** padnamelist_store(PADNAMELIST *pnl, SSize_t key, PADNAME *val)pad_tidyNOTE:pad_tidy isexperimental and may change or be removed without notice.
Tidy up a pad at the end of compilation of the code to which it belongs. Jobs performed here are: remove most stuff from the pads of anonsub prototypes; give it a@_; mark temporaries as such.type indicates the kind of subroutine:
padtidy_SUB ordinary subroutinepadtidy_SUBCLONE prototype for lexical closurepadtidy_FORMAT formatvoid pad_tidy(padtidy_type type)PERL_ASYNC_CHECKDescribed inperlinterp.
void PERL_ASYNC_CHECK()perl_cloneCreate and return a new interpreter by cloning the current one.
perl_clone takes these flags as parameters:
CLONEf_COPY_STACKS - is used to, well, copy the stacks also, without it we only clone the data and zero the stacks, with it we copy the stacks and the new perl interpreter is ready to run at the exact same point as the previous one. The pseudo-fork code usesCOPY_STACKS while the threads->create doesn't.
CLONEf_KEEP_PTR_TABLE -perl_clone keeps a ptr_table with the pointer of the old variable as a key and the new variable as a value, this allows it to check if something has been cloned and not clone it again, but rather just use the value and increase the refcount. IfKEEP_PTR_TABLE is not set thenperl_clone will kill the ptr_table using the functionptr_table_free(PL_ptr_table); PL_ptr_table = NULL;. A reason to keep it around is if you want to dup some of your own variables which are outside the graph that perl scans.
CLONEf_CLONE_HOST - This is a win32 thing, it is ignored on unix, it tells perl's win32host code (which is c++) to clone itself, this is needed on win32 if you want to run two threads at the same time, if you just want to do some stuff in a separate perl interpreter and then throw it away and return to the original one, you don't need to do anything.
PerlInterpreter * perl_clone(PerlInterpreter *proto_perl, UV flags)perl_constructInitializes a new Perl interpreter. Seeperlembed.
void perl_construct(PerlInterpreter *my_perl)perl_destructShuts down a Perl interpreter. Seeperlembed for a tutorial.
my_perl points to the Perl interpreter. It must have been previously created through the use of"perl_alloc" and"perl_construct". It may have been initialised through"perl_parse", and may have been used through"perl_run" and other means. This function should be called for any Perl interpreter that has been constructed with"perl_construct", even if subsequent operations on it failed, for example if"perl_parse" returned a non-zero value.
If the interpreter'sPL_exit_flags word has thePERL_EXIT_DESTRUCT_END flag set, then this function will execute code inEND blocks before performing the rest of destruction. If it is desired to make any use of the interpreter between"perl_parse" and"perl_destruct" other than just calling"perl_run", then this flag should be set early on. This matters if"perl_run" will not be called, or if anything else will be done in addition to calling"perl_run".
Returns a value be a suitable value to pass to the C library functionexit (or to return frommain), to serve as an exit code indicating the nature of the way the interpreter terminated. This takes into account any failure of"perl_parse" and any early exit from"perl_run". The exit code is of the type required by the host operating system, so because of differing exit code conventions it is not portable to interpret specific numeric values as having specific meanings.
int perl_destruct(PerlInterpreter *my_perl)perl_parseTells a Perl interpreter to parse a Perl script. This performs most of the initialisation of a Perl interpreter. Seeperlembed for a tutorial.
my_perl points to the Perl interpreter that is to parse the script. It must have been previously created through the use of"perl_alloc" and"perl_construct".xsinit points to a callback function that will be called to set up the ability for this Perl interpreter to load XS extensions, or may be null to perform no such setup.
argc andargv supply a set of command-line arguments to the Perl interpreter, as would normally be passed to themain function of a C program.argv[argc] must be null. These arguments are where the script to parse is specified, either by naming a script file or by providing a script in a-e option. If$0 will be written to in the Perl interpreter, then the argument strings must be in writable memory, and so mustn't just be string constants.
env specifies a set of environment variables that will be used by this Perl interpreter. If non-null, it must point to a null-terminated array of environment strings. If null, the Perl interpreter will use the environment supplied by theenviron global variable.
This function initialises the interpreter, and parses and compiles the script specified by the command-line arguments. This includes executing code inBEGIN,UNITCHECK, andCHECK blocks. It does not executeINIT blocks or the main program.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether there was a failure in initialisation. If zero is returned, this indicates that initialisation was successful, and it is safe to proceed to call"perl_run" and make other use of it. If a non-zero value is returned, this indicates some problem that means the interpreter wants to terminate. The interpreter should not be just abandoned upon such failure; the caller should proceed to shut the interpreter down cleanly with"perl_destruct" and free it with"perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library functionexit (or to return frommain), to serve as an exit code indicating the nature of the way initialisation terminated. However, this isn't portable, due to differing exit code conventions. An attempt is made to return an exit code of the type required by the host operating system, but because it is constrained to be non-zero, it is not necessarily possible to indicate every type of exit. It is only reliable on Unix, where a zero exit code can be augmented with a set bit that will be ignored. In any case, this function is not the correct place to acquire an exit code: one should get that from"perl_destruct".
int perl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit, int argc, char **argv, char **env)perl_runTells a Perl interpreter to run its main program. Seeperlembed for a tutorial.
my_perl points to the Perl interpreter. It must have been previously created through the use of"perl_alloc" and"perl_construct", and initialised through"perl_parse". This function should not be called if"perl_parse" returned a non-zero value, indicating a failure in initialisation or compilation.
This function executes code inINIT blocks, and then executes the main program. The code to be executed is that established by the prior call to"perl_parse". If the interpreter'sPL_exit_flags word does not have thePERL_EXIT_DESTRUCT_END flag set, then this function will also execute code inEND blocks. If it is desired to make any further use of the interpreter after calling this function, thenEND blocks should be postponed to"perl_destruct" time by setting that flag.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether the program terminated non-locally. If zero is returned, this indicates that the program ran to completion, and it is safe to make other use of the interpreter (provided that thePERL_EXIT_DESTRUCT_END flag was set as described above). If a non-zero value is returned, this indicates that the interpreter wants to terminate early. The interpreter should not be just abandoned because of this desire to terminate; the caller should proceed to shut the interpreter down cleanly with"perl_destruct" and free it with"perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library functionexit (or to return frommain), to serve as an exit code indicating the nature of the way the program terminated. However, this isn't portable, due to differing exit code conventions. An attempt is made to return an exit code of the type required by the host operating system, but because it is constrained to be non-zero, it is not necessarily possible to indicate every type of exit. It is only reliable on Unix, where a zero exit code can be augmented with a set bit that will be ignored. In any case, this function is not the correct place to acquire an exit code: one should get that from"perl_destruct".
int perl_run(PerlInterpreter *my_perl)PERL_SYS_INITPERL_SYS_INIT3These provide system-specific tune up of the C runtime environment necessary to run Perl interpreters. Only one should be used, and it should be called only once, before creating any Perl interpreters.
They differ in thatPERL_SYS_INIT3 also initializesenv.
void PERL_SYS_INIT (int *argc, char*** argv)void PERL_SYS_INIT3(int *argc, char*** argv, char*** env)PERL_SYS_TERMProvides system-specific clean up of the C runtime environment after running Perl interpreters. This should be called only once, after freeing any remaining Perl interpreters.
void PERL_SYS_TERM()PL_exit_flagsContains flags controlling perl's behaviour on exit():
PERL_EXIT_DESTRUCT_END
If set, END blocks are executed when the interpreter is destroyed. This is normally set by perl itself after the interpreter is constructed.
PERL_EXIT_ABORT
Callabort() on exit. This is used internally by perl itself to abort if exit is called while processing exit.
PERL_EXIT_WARN
Warn on exit.
PERL_EXIT_EXPECTED
Set by the"exit" in perlfunc operator.
U8 PL_exit_flagsPL_perl_destruct_levelThis value may be set when embedding for full cleanup.
Possible values:
0 - none
1 - full
2 or greater - full with checks.
If$ENV{PERL_DESTRUCT_LEVEL} is set to an integer greater than the value ofPL_perl_destruct_level its value is used instead.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
signed char PL_perl_destruct_levelptr_table_fetchLook forsv in the pointer-mapping tabletbl, returning its value, or NULL if not found.
void * ptr_table_fetch(PTR_TBL_t * const tbl, const void * const sv)ptr_table_freeClear and free a ptr table
void ptr_table_free(PTR_TBL_t * const tbl)ptr_table_newCreate a new pointer-mapping table
PTR_TBL_t * ptr_table_new()ptr_table_splitDouble the hash bucket size of an existing ptr table
void ptr_table_split(PTR_TBL_t * const tbl)ptr_table_storeAdd a new entry to a pointer-mapping tabletbl. In hash terms,oldsv is the key; Cnewsv> is the value.
The names "old" and "new" are specific to the core's typical use of ptr_tables in thread cloning.
void ptr_table_store(PTR_TBL_t * const tbl, const void * const oldsv, void * const newsv)require_pvTells Perl torequire the file named by the string argument. It is analogous to the Perl codeeval "require '$file'". It's even implemented that way; consider using load_module instead.
NOTE: theperl_require_pv() form isdeprecated.
void require_pv(const char *pv)vload_moduleLike"load_module" but the arguments are an encapsulated argument list.
void vload_module(U32 flags, SV *name, SV *ver, va_list *args)sv_string_from_errnumGenerates the message string describing an OS error and returns it as an SV.errnum must be a value thaterrno could take, identifying the type of error.
Iftgtsv is non-null then the string will be written into that SV (overwriting existing content) and it will be returned. Iftgtsv is a null pointer then the string will be written into a new mortal SV which will be returned.
The message will be taken from whatever locale would be used by$!, and will be encoded in the SV in whatever manner would be used by$!. The details of this process are subject to future change. Currently, the message is taken from the C locale by default (usually producing an English message), and from the currently selected locale when in the scope of theuse locale pragma. A heuristic attempt is made to decode the message from the locale's character encoding, but it will only be decoded as either UTF-8 or ISO-8859-1. It is always correctly decoded in a UTF-8 locale, usually in an ISO-8859-1 locale, and never in any other locale.
The SV is always returned containing an actual string, and with no other OK bits set. Unlike$!, a message is even yielded forerrnum zero (meaning success), and if no useful message is available then a useless string (currently empty) is returned.
SV * sv_string_from_errnum(int errnum, SV *tgtsv)dXCPTSet up necessary local variables for exception handling. See"Exception Handling" in perlguts.
dXCPT;JMPENV_JUMPDescribed inperlinterp.
void JMPENV_JUMP(int v)JMPENV_PUSHDescribed inperlinterp.
void JMPENV_PUSH(int v)PL_restartopDescribed inperlinterp.
XCPT_CATCHIntroduces a catch block. See"Exception Handling" in perlguts.
XCPT_RETHROWRethrows a previously caught exception. See"Exception Handling" in perlguts.
XCPT_RETHROW;XCPT_TRY_ENDEnds a try block. See"Exception Handling" in perlguts.
XCPT_TRY_STARTStarts a try block. See"Exception Handling" in perlguts.
Also see"List of capability HAS_foo symbols".
DIRNAMLENThis symbol, if defined, indicates to the C program that the length of directory entry names is provided by ad_namlen field. Otherwise you need to dostrlen() on thed_name field.
DOSUIDThis symbol, if defined, indicates that the C program should check the script that it is executing for setuid/setgid bits, and attempt to emulate setuid/setgid on systems that have disabled setuid #! scripts because the kernel can't do it securely. It is up to the package designer to make sure that this emulation is done securely. Among other things, it should do an fstat on the script it just opened to make sure it really is a setuid/setgid script, it should make sure the arguments passed correspond exactly to the argument on the #! line, and it should not trust any subprocesses to which it must pass the filename rather than the file descriptor of the script to be executed.
EOF_NONBLOCKThis symbol, if defined, indicates to the C program that aread() on a non-blocking file descriptor will return 0 onEOF, and not the value held inRD_NODATA (-1 usually, in that case!).
FCNTL_CAN_LOCKThis symbol, if defined, indicates thatfcntl() can be used for file locking. Normally on Unix systems this is defined. It may be undefined onVMS.
FFLUSH_ALLThis symbol, if defined, tells that to flush all pending stdio output one must loop through all the stdio file handles stored in an array and fflush them. Note that iffflushNULL is defined, fflushall will not even be probed for and will be left undefined.
FFLUSH_NULLThis symbol, if defined, tells thatfflush(NULL) correctly flushes all pending stdio output without side effects. In particular, on some platforms callingfflush(NULL) *still* corruptsSTDIN if it is a pipe.
FILE_baseThis macro is used to access the_base field (or equivalent) of theFILE structure pointed to by its argument. This macro will always be defined ifUSE_STDIO_BASE is defined.
void * FILE_base(FILE * f)FILE_bufsizThis macro is used to determine the number of bytes in the I/O buffer pointed to by_base field (or equivalent) of theFILE structure pointed to its argument. This macro will always be defined ifUSE_STDIO_BASE is defined.
Size_t FILE_bufsiz(FILE *f)FILE_cntThis macro is used to access the_cnt field (or equivalent) of theFILE structure pointed to by its argument. This macro will always be defined ifUSE_STDIO_PTR is defined.
Size_t FILE_cnt(FILE * f)FILE_ptrThis macro is used to access the_ptr field (or equivalent) of theFILE structure pointed to by its argument. This macro will always be defined ifUSE_STDIO_PTR is defined.
void * FILE_ptr(FILE * f)FLEXFILENAMESThis symbol, if defined, indicates that the system supports filenames longer than 14 characters.
HAS_DIR_DD_FDThis symbol, if defined, indicates that theDIR* dirstream structure contains a member variable nameddd_fd.
HAS_DUP2This symbol, if defined, indicates that thedup2 routine is available to duplicate file descriptors.
HAS_DUP3This symbol, if defined, indicates that thedup3 routine is available to duplicate file descriptors.
HAS_FAST_STDIOThis symbol, if defined, indicates that the "fast stdio" is available to manipulate the stdio buffers directly.
HAS_FCHDIRThis symbol, if defined, indicates that thefchdir routine is available to change directory using a file descriptor.
HAS_FCNTLThis symbol, if defined, indicates to the C program that thefcntl() function exists.
HAS_FDCLOSEThis symbol, if defined, indicates that thefdclose routine is available to free aFILE structure without closing the underlying file descriptor. This function appeared inFreeBSD 10.2.
HAS_FPATHCONFThis symbol, if defined, indicates thatpathconf() is available to determine file-system related limits and options associated with a given open file descriptor.
HAS_FPOS64_TThis symbol will be defined if the C compiler supportsfpos64_t.
HAS_FSTATFSThis symbol, if defined, indicates that thefstatfs routine is available to stat filesystems by file descriptors.
HAS_FSTATVFSThis symbol, if defined, indicates that thefstatvfs routine is available to stat filesystems by file descriptors.
HAS_GETFSSTATThis symbol, if defined, indicates that thegetfsstat routine is available to stat filesystems in bulk.
HAS_GETMNTThis symbol, if defined, indicates that thegetmnt routine is available to get filesystem mount info by filename.
HAS_GETMNTENTThis symbol, if defined, indicates that thegetmntent routine is available to iterate through mounted file systems to get their info.
HAS_HASMNTOPTThis symbol, if defined, indicates that thehasmntopt routine is available to query the mount options of file systems.
HAS_LSEEK_PROTOThis symbol, if defined, indicates that the system provides a prototype for thelseek() function. Otherwise, it is up to the program to supply one. A good guess is
extern off_t lseek(int, off_t, int);HAS_MKDIRThis symbol, if defined, indicates that themkdir routine is available to create directories. Otherwise you should fork off a new process to exec/bin/mkdir.
HAS_OFF64_TThis symbol will be defined if the C compiler supportsoff64_t.
HAS_OPENATThis symbol is defined if theopenat() routine is available.
HAS_OPEN3This manifest constant lets the C program know that the three argument form ofopen(2) is available.
HAS_POLLThis symbol, if defined, indicates that thepoll routine is available topoll active file descriptors. Please checkI_POLL andI_SYS_POLL to know which header should be included as well.
HAS_READDIRThis symbol, if defined, indicates that thereaddir routine is available to read directory entries. You may have to includedirent.h. See"I_DIRENT".
HAS_READDIR64_RThis symbol, if defined, indicates that thereaddir64_r routine is available to readdir64 re-entrantly.
HAS_REWINDDIRThis symbol, if defined, indicates that therewinddir routine is available. You may have to includedirent.h. See"I_DIRENT".
HAS_RMDIRThis symbol, if defined, indicates that thermdir routine is available to remove directories. Otherwise you should fork off a new process to exec/bin/rmdir.
HAS_SEEKDIRThis symbol, if defined, indicates that theseekdir routine is available. You may have to includedirent.h. See"I_DIRENT".
HAS_SELECTThis symbol, if defined, indicates that theselect routine is available toselect active file descriptors. If the timeout field is used,sys/time.h may need to be included.
HAS_SETVBUFThis symbol, if defined, indicates that thesetvbuf routine is available to change buffering on an open stdio stream. to a line-buffered mode.
HAS_STDIO_STREAM_ARRAYThis symbol, if defined, tells that there is an array holding the stdio streams.
HAS_STRUCT_FS_DATAThis symbol, if defined, indicates that thestruct fs_data to dostatfs() is supported.
HAS_STRUCT_STATFSThis symbol, if defined, indicates that thestruct statfs to dostatfs() is supported.
HAS_STRUCT_STATFS_F_FLAGSThis symbol, if defined, indicates that thestruct statfs does have thef_flags member containing the mount flags of the filesystem containing the file. This kind ofstruct statfs is coming fromsys/mount.h (BSD 4.3), not fromsys/statfs.h (SYSV). OlderBSDs (like Ultrix) do not havestatfs() andstruct statfs, they haveustat() andgetmnt() withstruct ustat andstruct fs_data.
HAS_TELLDIRThis symbol, if defined, indicates that thetelldir routine is available. You may have to includedirent.h. See"I_DIRENT".
HAS_USTATThis symbol, if defined, indicates that theustat system call is available to query file system statistics bydev_t.
I_FCNTLThis manifest constant tells the C program to includefcntl.h.
#ifdef I_FCNTL #include <fcntl.h>#endifI_SYS_DIRThis symbol, if defined, indicates to the C program that it should includesys/dir.h.
#ifdef I_SYS_DIR #include <sys_dir.h>#endifI_SYS_FILEThis symbol, if defined, indicates to the C program that it should includesys/file.h to get definition ofR_OK and friends.
#ifdef I_SYS_FILE #include <sys_file.h>#endifI_SYS_NDIRThis symbol, if defined, indicates to the C program that it should includesys/ndir.h.
#ifdef I_SYS_NDIR #include <sys_ndir.h>#endifI_SYS_STATFSThis symbol, if defined, indicates thatsys/statfs.h exists.
#ifdef I_SYS_STATFS #include <sys_statfs.h>#endifLSEEKSIZEThis symbol holds the number of bytes used by theOff_t.
RD_NODATAThis symbol holds the return code fromread() when no data is present on the non-blocking file descriptor. Be careful! IfEOF_NONBLOCK is not defined, then you can't distinguish between no data andEOF by issuing aread(). You'll have to find another way to tell for sure!
READDIR64_R_PROTOThis symbol encodes the prototype ofreaddir64_r. It is zero ifd_readdir64_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_readdir64_r is defined.
STDCHARThis symbol is defined to be the type of char used instdio.h. It has the values "unsigned char" or "char".
STDIO_CNT_LVALUEThis symbol is defined if theFILE_cnt macro can be used as an lvalue.
STDIO_PTR_LVAL_NOCHANGE_CNTThis symbol is defined if using theFILE_ptr macro as an lvalue to increase the pointer by n leavesFile_cnt(fp) unchanged.
STDIO_PTR_LVAL_SETS_CNTThis symbol is defined if using theFILE_ptr macro as an lvalue to increase the pointer by n has the side effect of decreasing the value ofFile_cnt(fp) by n.
STDIO_PTR_LVALUEThis symbol is defined if theFILE_ptr macro can be used as an lvalue.
STDIO_STREAM_ARRAYThis symbol tells the name of the array holding the stdio streams. Usual values include_iob,__iob, and__sF.
ST_INO_SIGNThis symbol holds the signedness ofstruct stat'sst_ino. 1 for unsigned, -1 for signed.
ST_INO_SIZEThis variable contains the size ofstruct stat'sst_ino in bytes.
VAL_EAGAINThis symbol holds the errno error code set byread() when no data was present on the non-blocking file descriptor.
VAL_O_NONBLOCKThis symbol is to be used duringopen() orfcntl(F_SETFL) to turn on non-blocking I/O for the file descriptor. Note that there is no way back, i.e. you cannot turn it blocking again this way. If you wish to alternatively switch between blocking and non-blocking, use theioctl(FIOSNBIO) call instead, but that is not supported by all devices.
VOID_CLOSEDIRThis symbol, if defined, indicates that theclosedir() routine does not return a value.
Also"List of capability HAS_foo symbols" lists capabilities that arent in this section. For exampleHAS_ASINH, for the hyperbolic sine function.
CASTFLAGSThis symbol contains flags that say what difficulties the compiler has casting odd floating values to unsigned long:
0 = ok1 = couldn't cast < 02 = couldn't cast >= 0x800000004 = couldn't cast in argument expression listCASTNEGFLOATThis symbol is defined if the C compiler can cast negative numbers to unsigned longs, ints and shorts.
DOUBLE_HAS_INFThis symbol, if defined, indicates that the double has the infinity.
DOUBLE_HAS_NANThis symbol, if defined, indicates that the double has the not-a-number.
DOUBLE_HAS_NEGATIVE_ZEROThis symbol, if defined, indicates that the double has thenegative_zero.
DOUBLE_HAS_SUBNORMALSThis symbol, if defined, indicates that the double has the subnormals (denormals).
DOUBLEINFBYTESThis symbol, if defined, is a comma-separated list of hexadecimal bytes for the double precision infinity.
DOUBLEKINDDOUBLEKIND will be one ofDOUBLE_IS_IEEE_754_32_BIT_LITTLE_ENDIANDOUBLE_IS_IEEE_754_32_BIT_BIG_ENDIANDOUBLE_IS_IEEE_754_64_BIT_LITTLE_ENDIANDOUBLE_IS_IEEE_754_64_BIT_BIG_ENDIANDOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIANDOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIANDOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_LE_BEDOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_BE_LEDOUBLE_IS_VAX_F_FLOATDOUBLE_IS_VAX_D_FLOATDOUBLE_IS_VAX_G_FLOATDOUBLE_IS_IBM_SINGLE_32_BITDOUBLE_IS_IBM_DOUBLE_64_BITDOUBLE_IS_CRAY_SINGLE_64_BITDOUBLE_IS_UNKNOWN_FORMAT
DOUBLEMANTBITSThis symbol, if defined, tells how many mantissa bits there are in double precision floating point format. Note that this is usuallyDBL_MANT_DIG minus one, since with the standardIEEE 754 formatsDBL_MANT_DIG includes the implicit bit, which doesn't really exist.
DOUBLENANBYTESThis symbol, if defined, is a comma-separated list of hexadecimal bytes (0xHH) for the double precision not-a-number.
DOUBLESIZEThis symbol contains the size of a double, so that the C preprocessor can make decisions based on it.
DOUBLE_STYLE_CRAYThis symbol, if defined, indicates that the double is the 64-bitCRAY mainframe format.
DOUBLE_STYLE_IBMThis symbol, if defined, indicates that the double is the 64-bitIBM mainframe format.
DOUBLE_STYLE_IEEEThis symbol, if defined, indicates that the double is the 64-bitIEEE 754.
DOUBLE_STYLE_VAXThis symbol, if defined, indicates that the double is the 64-bitVAX format D or G.
HAS_ATOLFThis symbol, if defined, indicates that theatolf routine is available to convert strings into long doubles.
HAS_CLASSThis symbol, if defined, indicates that theclass routine is available to classify doubles. Available for example inAIX. The returned values are defined infloat.h and are:
FP_PLUS_NORM Positive normalized, nonzeroFP_MINUS_NORM Negative normalized, nonzeroFP_PLUS_DENORM Positive denormalized, nonzeroFP_MINUS_DENORM Negative denormalized, nonzeroFP_PLUS_ZERO +0.0FP_MINUS_ZERO -0.0FP_PLUS_INF +INFFP_MINUS_INF -INFFP_NANS Signaling Not a Number (NaNS)FP_NANQ Quiet Not a Number (NaNQ)HAS_FINITEThis symbol, if defined, indicates that thefinite routine is available to check whether a double isfinite (non-infinity non-NaN).
HAS_FINITELThis symbol, if defined, indicates that thefinitel routine is available to check whether a long double is finite (non-infinity non-NaN).
HAS_FPCLASSThis symbol, if defined, indicates that thefpclass routine is available to classify doubles. Available for example in Solaris/SVR4. The returned values are defined inieeefp.h and are:
FP_SNAN signaling NaNFP_QNAN quiet NaNFP_NINF negative infinityFP_PINF positive infinityFP_NDENORM negative denormalized non-zeroFP_PDENORM positive denormalized non-zeroFP_NZERO negative zeroFP_PZERO positive zeroFP_NNORM negative normalized non-zeroFP_PNORM positive normalized non-zeroHAS_FP_CLASSThis symbol, if defined, indicates that thefp_class routine is available to classify doubles. Available for example in DigitalUNIX. The returned values are defined inmath.h and are:
FP_SNAN Signaling NaN (Not-a-Number)FP_QNAN Quiet NaN (Not-a-Number)FP_POS_INF +infinityFP_NEG_INF -infinityFP_POS_NORM Positive normalizedFP_NEG_NORM Negative normalizedFP_POS_DENORM Positive denormalizedFP_NEG_DENORM Negative denormalizedFP_POS_ZERO +0.0 (positive zero)FP_NEG_ZERO -0.0 (negative zero)HAS_FPCLASSIFYThis symbol, if defined, indicates that thefpclassify routine is available to classify doubles. Available for example in HP-UX. The returned values are defined inmath.h and are
FP_NORMAL NormalizedFP_ZERO ZeroFP_INFINITE InfinityFP_SUBNORMAL DenormalizedFP_NAN NaNHAS_FP_CLASSIFYThis symbol, if defined, indicates that thefp_classify routine is available to classify doubles. The values are defined inmath.h
FP_NORMAL NormalizedFP_ZERO ZeroFP_INFINITE InfinityFP_SUBNORMAL DenormalizedFP_NAN NaNHAS_FPCLASSLThis symbol, if defined, indicates that thefpclassl routine is available to classify long doubles. Available for example inIRIX. The returned values are defined inieeefp.h and are:
FP_SNAN signaling NaNFP_QNAN quiet NaNFP_NINF negative infinityFP_PINF positive infinityFP_NDENORM negative denormalized non-zeroFP_PDENORM positive denormalized non-zeroFP_NZERO negative zeroFP_PZERO positive zeroFP_NNORM negative normalized non-zeroFP_PNORM positive normalized non-zeroHAS_FP_CLASSLThis symbol, if defined, indicates that thefp_classl routine is available to classify long doubles. Available for example in DigitalUNIX. See for possible valuesHAS_FP_CLASS.
HAS_FPGETROUNDThis symbol, if defined, indicates that thefpgetround routine is available to get the floating point rounding mode.
HAS_FREXPLThis symbol, if defined, indicates that thefrexpl routine is available to break a long double floating-point number into a normalized fraction and an integral power of 2.
HAS_ILOGBThis symbol, if defined, indicates that theilogb routine is available to get integer exponent of a floating-point value.
HAS_ISFINITEThis symbol, if defined, indicates that theisfinite routine is available to check whether a double is finite (non-infinity non-NaN).
HAS_ISFINITELThis symbol, if defined, indicates that theisfinitel routine is available to check whether a long double is finite. (non-infinity non-NaN).
HAS_ISINFThis symbol, if defined, indicates that theisinf routine is available to check whether a double is an infinity.
HAS_ISINFLThis symbol, if defined, indicates that theisinfl routine is available to check whether a long double is an infinity.
HAS_ISNANThis symbol, if defined, indicates that theisnan routine is available to check whether a double is a NaN.
HAS_ISNANLThis symbol, if defined, indicates that theisnanl routine is available to check whether a long double is a NaN.
HAS_ISNORMALThis symbol, if defined, indicates that theisnormal routine is available to check whether a double is normal (non-zero normalized).
HAS_J0LThis symbol, if defined, indicates to the C program that thej0l() function is available for Bessel functions of the first kind of the order zero, for long doubles.
HAS_J0This symbol, if defined, indicates to the C program that thej0() function is available for Bessel functions of the first kind of the order zero, for doubles.
HAS_LDBL_DIGThis symbol, if defined, indicates that this system'sfloat.h orlimits.h defines the symbolLDBL_DIG, which is the number of significant digits in a long double precision number. Unlike forDBL_DIG, there's no good guess forLDBL_DIG if it is undefined.
HAS_LDEXPLThis symbol, if defined, indicates that theldexpl routine is available to shift a long double floating-point number by an integral power of 2.
HAS_LLRINTThis symbol, if defined, indicates that thellrint routine is available to return the long long value closest to a double (according to the current rounding mode).
HAS_LLRINTLThis symbol, if defined, indicates that thellrintl routine is available to return the long long value closest to a long double (according to the current rounding mode).
HAS_LLROUNDLThis symbol, if defined, indicates that thellroundl routine is available to return the nearest long long value away from zero of the long double argument value.
HAS_LONG_DOUBLEThis symbol will be defined if the C compiler supports long doubles.
HAS_LRINTThis symbol, if defined, indicates that thelrint routine is available to return the integral value closest to a double (according to the current rounding mode).
HAS_LRINTLThis symbol, if defined, indicates that thelrintl routine is available to return the integral value closest to a long double (according to the current rounding mode).
HAS_LROUNDLThis symbol, if defined, indicates that thelroundl routine is available to return the nearest integral value away from zero of the long double argument value.
HAS_MODFLThis symbol, if defined, indicates that themodfl routine is available to split a long double x into a fractional part f and an integer part i such that |f| < 1.0 and (f + i) = x.
HAS_NANThis symbol, if defined, indicates that thenan routine is available to generate NaN.
HAS_NEXTTOWARDThis symbol, if defined, indicates that thenexttoward routine is available to return the next machine representable long double from x in direction y.
HAS_REMAINDERThis symbol, if defined, indicates that theremainder routine is available to return the floating-pointremainder.
HAS_SCALBNThis symbol, if defined, indicates that thescalbn routine is available to multiply floating-point number by integral power of radix.
HAS_SIGNBITThis symbol, if defined, indicates that thesignbit routine is available to check if the given number has the sign bit set. This should include correct testing of -0.0. This will only be set if thesignbit() routine is safe to use with the NV type used internally in perl. Users should callPerl_signbit(), which will be #defined to the system'ssignbit() function or macro if this symbol is defined.
HAS_SQRTLThis symbol, if defined, indicates that thesqrtl routine is available to do long double square roots.
HAS_STRTOD_LThis symbol, if defined, indicates that thestrtod_l routine is available to convert strings to long doubles.
HAS_STRTOLDThis symbol, if defined, indicates that thestrtold routine is available to convert strings to long doubles.
HAS_STRTOLD_LThis symbol, if defined, indicates that thestrtold_l routine is available to convert strings to long doubles.
HAS_TRUNCThis symbol, if defined, indicates that thetrunc routine is available to round doubles towards zero.
HAS_UNORDEREDThis symbol, if defined, indicates that theunordered routine is available to check whether two doubles areunordered (effectively: whether either of them is NaN)
I_FENVThis symbol, if defined, indicates to the C program that it should includefenv.h to get the floating point environment definitions.
#ifdef I_FENV #include <fenv.h>#endifI_QUADMATHThis symbol, if defined, indicates thatquadmath.h exists and should be included.
#ifdef I_QUADMATH #include <quadmath.h>#endifLONGDBLINFBYTESThis symbol, if defined, is a comma-separated list of hexadecimal bytes for the long double precision infinity.
LONGDBLMANTBITSThis symbol, if defined, tells how many mantissa bits there are in long double precision floating point format. Note that this can beLDBL_MANT_DIG minus one, sinceLDBL_MANT_DIG can include theIEEE 754 implicit bit. The common x86-style 80-bit long double does not have an implicit bit.
LONGDBLNANBYTESThis symbol, if defined, is a comma-separated list of hexadecimal bytes (0xHH) for the long double precision not-a-number.
LONG_DOUBLEKINDLONG_DOUBLEKIND will be one ofLONG_DOUBLE_IS_DOUBLELONG_DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIANLONG_DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIANLONG_DOUBLE_IS_X86_80_BIT_LITTLE_ENDIANLONG_DOUBLE_IS_X86_80_BIT_BIG_ENDIANLONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_LELONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_BELONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_BELONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_LELONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LITTLE_ENDIANLONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BIG_ENDIANLONG_DOUBLE_IS_VAX_H_FLOATLONG_DOUBLE_IS_UNKNOWN_FORMAT It is only defined if the system supports long doubles.
LONG_DOUBLESIZEThis symbol contains the size of a long double, so that the C preprocessor can make decisions based on it. It is only defined if the system supports long doubles. Note that this issizeof(long double), which may include unused bytes.
LONG_DOUBLE_STYLE_IEEEThis symbol, if defined, indicates that the long double is any of theIEEE 754 style long doubles:LONG_DOUBLE_STYLE_IEEE_STD,LONG_DOUBLE_STYLE_IEEE_EXTENDED,LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE.
LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLEThis symbol, if defined, indicates that the long double is the 128-bit double-double.
LONG_DOUBLE_STYLE_IEEE_EXTENDEDThis symbol, if defined, indicates that the long double is the 80-bitIEEE 754. Note that despite the 'extended' this is less than the 'std', since this is an extension of the double precision.
LONG_DOUBLE_STYLE_IEEE_STDThis symbol, if defined, indicates that the long double is the 128-bitIEEE 754.
LONG_DOUBLE_STYLE_VAXThis symbol, if defined, indicates that the long double is the 128-bitVAX format H.
NVMANTBITSThis symbol, if defined, tells how many mantissa bits (not including implicit bit) there are in a Perl NV. This depends on which floating point type was chosen.
NV_OVERFLOWS_INTEGERS_ATThis symbol gives the largest integer value that NVs can hold. This value + 1.0 cannot be stored accurately. It is expressed as constant floating point expression to reduce the chance of decimal/binary conversion issues. If it can not be determined, the value 0 is given.
NV_PRESERVES_UVThis symbol, if defined, indicates that a variable of typeNVTYPE can preserve all the bits of a variable of typeUVTYPE.
NV_PRESERVES_UV_BITSThis symbol contains the number of bits a variable of typeNVTYPE can preserve of a variable of typeUVTYPE.
NVSIZEThis symbol contains thesizeof(NV). Note that some floating point formats have unused bytes. The most notable example is the x86* 80-bit extended precision which comes in byte sizes of 12 and 16 (for 32 and 64 bit platforms, respectively), but which only uses 10 bytes. Perl compiled with-Duselongdouble on x86* is like this.
NVTYPEThis symbol defines the C type used for Perl's NV.
NV_ZERO_IS_ALLBITS_ZEROThis symbol, if defined, indicates that a variable of typeNVTYPE stores 0.0 in memory as all bits zero.
This section contains configuration information not otherwise found in the more specialized sections of this document. At the end is a list of#defines whose name should be enough to tell you what they do, and a list of #defines which tell you if you need to#include files to get the corresponding functionality.
ASCIIishA preprocessor symbol that is defined iff the system is an ASCII platform; this symbol would not be defined on"EBCDIC" platforms.
#ifdef ASCIIishBYTEORDERThis symbol holds the hexadecimal constant defined in byteorder, in a UV, i.e. 0x1234 or 0x4321 or 0x12345678, etc... If the compiler supports cross-compiling or multiple-architecture binaries, use compiler-defined macros to determine the byte order.
CHARBITSThis symbol contains the size of a char, so that the C preprocessor can make decisions based on it.
DB_VERSION_MAJOR_CFGThis symbol, if defined, defines the major version number of Berkeley DB found in thedb.h header when Perl was configured.
DB_VERSION_MINOR_CFGThis symbol, if defined, defines the minor version number of Berkeley DB found in thedb.h header when Perl was configured. For DB version 1 this is always 0.
DB_VERSION_PATCH_CFGThis symbol, if defined, defines the patch version number of Berkeley DB found in thedb.h header when Perl was configured. For DB version 1 this is always 0.
DEFAULT_INC_EXCLUDES_DOTThis symbol, if defined, removes the legacy default behavior of including '.' at the end of @INC.
DLSYM_NEEDS_UNDERSCOREThis symbol, if defined, indicates that we need to prepend an underscore to the symbol name before callingdlsym(). This only makes sense if you *have* dlsym, which we will presume is the case if you're usingdl_dlopen.xs.
EBCDICThis symbol, if defined, indicates that this system usesEBCDIC encoding.
HAS_CSHThis symbol, if defined, indicates that the C-shell exists.
HAS_GETHOSTNAMEThis symbol, if defined, indicates that the C program may use thegethostname() routine to derive the host name. See also"HAS_UNAME" and"PHOSTNAME".
HAS_GNULIBCThis symbol, if defined, indicates to the C program that theGNU C library is being used. A better check is to use the__GLIBC__ and__GLIBC_MINOR__ symbols supplied with glibc.
HAS_LGAMMAThis symbol, if defined, indicates that thelgamma routine is available to do the log gamma function. See also"HAS_TGAMMA" and"HAS_LGAMMA_R".
HAS_LGAMMA_RThis symbol, if defined, indicates that thelgamma_r routine is available to do the log gamma function without using the global signgam variable.
HAS_NON_INT_BITFIELDSThis symbol, if defined, indicates that the C compiler accepts, without error or warning,struct bitfields that are declared with sizes other than plain 'int'; for example 'unsigned char' is accepted.
HAS_PRCTL_SET_NAMEThis symbol, if defined, indicates that the prctl routine is available to set process title and supportsPR_SET_NAME.
HAS_PROCSELFEXEThis symbol is defined ifPROCSELFEXE_PATH is a symlink to the absolute pathname of the executing program.
HAS_PSEUDOFORKThis symbol, if defined, indicates that an emulation of the fork routine is available.
HAS_REGCOMPThis symbol, if defined, indicates that theregcomp() routine is available to do some regular pattern matching (usually onPOSIX.2 conforming systems).
HAS_SETPGIDThis symbol, if defined, indicates that thesetpgid(pid, gpid) routine is available to set process group ID.
HAS_SIGSETJMPThis variable indicates to the C program that thesigsetjmp() routine is available to save the calling process's registers and stack environment for later use bysiglongjmp(), and to optionally save the process's signal mask. See"Sigjmp_buf","Sigsetjmp", and"Siglongjmp".
HAS_STRUCT_CMSGHDRThis symbol, if defined, indicates that thestruct cmsghdr is supported.
HAS_STRUCT_MSGHDRThis symbol, if defined, indicates that thestruct msghdr is supported.
HAS_TGAMMAThis symbol, if defined, indicates that thetgamma routine is available to do the gamma function. See also"HAS_LGAMMA".
HAS_UNAMEThis symbol, if defined, indicates that the C program may use theuname() routine to derive the host name. See also"HAS_GETHOSTNAME" and"PHOSTNAME".
HAS_UNION_SEMUNThis symbol, if defined, indicates that theunion semun is defined by includingsys/sem.h. If not, the user code probably needs to define it as:
union semun {int val;struct semid_ds *buf;unsigned short *array;}I_DIRENTThis symbol, if defined, indicates to the C program that it should includedirent.h. Using this symbol also triggers the definition of theDirentry_t define which ends up being 'struct dirent' or 'struct direct' depending on the availability ofdirent.h.
#ifdef I_DIRENT #include <dirent.h>#endifI_POLLThis symbol, if defined, indicates thatpoll.h exists and should be included. (see also"HAS_POLL")
#ifdef I_POLL #include <poll.h>#endifI_SYS_RESOURCEThis symbol, if defined, indicates to the C program that it should includesys/resource.h.
#ifdef I_SYS_RESOURCE #include <sys_resource.h>#endifLIBM_LIB_VERSIONThis symbol, if defined, indicates that libm exports_LIB_VERSION and thatmath.h defines the enum to manipulate it.
NEED_VA_COPYThis symbol, if defined, indicates that the system stores the variable argument list datatype,va_list, in a format that cannot be copied by simple assignment, so that some other means must be used when copying is required. As such systems vary in their provision (or non-provision) of copying mechanisms,handy.h defines a platform- independent macro,Perl_va_copy(src, dst), to do the job.
OSNAMEThis symbol contains the name of the operating system, as determined by Configure. You shouldn't rely on it too much; the specific feature tests from Configure are generally more reliable.
OSVERSThis symbol contains the version of the operating system, as determined by Configure. You shouldn't rely on it too much; the specific feature tests from Configure are generally more reliable.
PERL_USE_GCC_BRACE_GROUPSThis C pre-processor value, if defined, indicates that it is permissible to use the GCC brace groups extension. However, use of this extension is DISCOURAGED. Use astatic inline function instead.
The extension, of the form
({ statement ... })turns the block consisting ofstatement ... into an expression with a value, unlike plain C language blocks. This can present optimization possibilities,BUT, unless you know for sure that this will never be compiled without this extension being available and not forbidden, you need to specify an alternative. Thus two code paths have to be maintained, which can get out-of-sync. All these issues are solved by using astatic inline function instead.
Perl can be configured to not use this feature by passing the parameter-Accflags=-DPERL_GCC_BRACE_GROUPS_FORBIDDEN toConfigure.
#ifdef PERL_USE_GCC_BRACE_GROUPSPHOSTNAMEThis symbol, if defined, indicates the command to feed to thepopen() routine to derive the host name. See also"HAS_GETHOSTNAME" and"HAS_UNAME". Note that the command uses a fully qualified path, so that it is safe even if used by a process with super-user privileges.
PROCSELFEXE_PATHIfHAS_PROCSELFEXE is defined this symbol is the filename of the symbolic link pointing to the absolute pathname of the executing program.
PTRSIZEThis symbol contains the size of a pointer, so that the C preprocessor can make decisions based on it. It will besizeof(void *) if the compiler supports (void *); otherwise it will besizeof(char *).
RANDBITSThis symbol indicates how many bits are produced by the function used to generate normalized random numbers. Values include 15, 16, 31, and 48.
SELECT_MIN_BITSThis symbol holds the minimum number of bits operated by select. That is, if you doselect(n, ...), how many bits at least will be cleared in the masks if some activity is detected. Usually this is either n or 32*ceil(n/32), especially many little-endians do the latter. This is only useful if you haveselect(), naturally.
SETUID_SCRIPTS_ARE_SECURE_NOWThis symbol, if defined, indicates that the bug that prevents setuid scripts from being secure is not present in this kernel.
ST_DEV_SIGNThis symbol holds the signedness ofstruct stat'sst_dev. 1 for unsigned, -1 for signed.
ST_DEV_SIZEThis variable contains the size ofstruct stat'sst_dev in bytes.
HAS_foo symbolsThis is a list of those symbols that dont appear elsewhere in ths document that indicate if the current platform has a certain capability. Their names all begin withHAS_. Only those symbols whose capability is directly derived from the name are listed here. All others have their meaning expanded out elsewhere in this document. This (relatively) compact list is because we think that the expansion would add little or no value and take up a lot of space (because there are so many). If you think certain ones should be expanded, send email toperl5-porters@perl.org.
Each symbol here will be#defined if and only if the platform has the capability. If you need more detail, see the corresponding entry inconfig.h. For convenience, the list is split so that the ones that indicate there is a reentrant version of a capability are listed separately
HAS_ACCEPT4,HAS_ACCESS,HAS_ACCESSX,HAS_ACOSH,HAS_AINTL,HAS_ALARM,HAS_ASINH,HAS_ATANH,HAS_ATOLL,HAS_CBRT,HAS_CHOWN,HAS_CHROOT,HAS_CHSIZE,HAS_CLEARENV,HAS_COPYSIGN,HAS_COPYSIGNL,HAS_CRYPT,HAS_CTERMID,HAS_CUSERID,HAS_DIRFD,HAS_DLADDR,HAS_DLERROR,HAS_EACCESS,HAS_ENDHOSTENT,HAS_ENDNETENT,HAS_ENDPROTOENT,HAS_ENDSERVENT,HAS_ERF,HAS_ERFC,HAS_EXPM1,HAS_EXP2,HAS_FCHMOD,HAS_FCHMODAT,HAS_FCHOWN,HAS_FDIM,HAS_FD_SET,HAS_FEGETROUND,HAS_FFS,HAS_FFSL,HAS_FGETPOS,HAS_FLOCK,HAS_FMA,HAS_FMAX,HAS_FMIN,HAS_FORK,HAS_FSEEKO,HAS_FSETPOS,HAS_FSYNC,HAS_FTELLO,HAS__FWALK,HAS_GAI_STRERROR,HAS_GETADDRINFO,HAS_GETCWD,HAS_GETESPWNAM,HAS_GETGROUPS,HAS_GETHOSTBYADDR,HAS_GETHOSTBYNAME,HAS_GETHOSTENT,HAS_GETLOGIN,HAS_GETNAMEINFO,HAS_GETNETBYADDR,HAS_GETNETBYNAME,HAS_GETNETENT,HAS_GETPAGESIZE,HAS_GETPGID,HAS_GETPGRP,HAS_GETPGRP2,HAS_GETPPID,HAS_GETPRIORITY,HAS_GETPROTOBYNAME,HAS_GETPROTOBYNUMBER,HAS_GETPROTOENT,HAS_GETPRPWNAM,HAS_GETSERVBYNAME,HAS_GETSERVBYPORT,HAS_GETSERVENT,HAS_GETSPNAM,HAS_HTONL,HAS_HTONS,HAS_HYPOT,HAS_ILOGBL,HAS_INET_ATON,HAS_INETNTOP,HAS_INETPTON,HAS_IP_MREQ,HAS_IP_MREQ_SOURCE,HAS_IPV6_MREQ,HAS_IPV6_MREQ_SOURCE,HAS_ISASCII,HAS_ISBLANK,HAS_ISLESS,HAS_KILLPG,HAS_LCHOWN,HAS_LINK,HAS_LINKAT,HAS_LLROUND,HAS_LOCKF,HAS_LOGB,HAS_LOG1P,HAS_LOG2,HAS_LROUND,HAS_LSTAT,HAS_MADVISE,HAS_MBLEN,HAS_MBRLEN,HAS_MBRTOWC,HAS_MBSTOWCS,HAS_MBTOWC,HAS_MEMMEM,HAS_MEMRCHR,HAS_MKDTEMP,HAS_MKFIFO,HAS_MKOSTEMP,HAS_MKSTEMP,HAS_MKSTEMPS,HAS_MMAP,HAS_MPROTECT,HAS_MSG,HAS_MSYNC,HAS_MUNMAP,HAS_NEARBYINT,HAS_NEXTAFTER,HAS_NICE,HAS_NTOHL,HAS_NTOHS,HAS_PATHCONF,HAS_PAUSE,HAS_PHOSTNAME,HAS_PIPE,HAS_PIPE2,HAS_PRCTL,HAS_PTRDIFF_T,HAS_READLINK,HAS_READV,HAS_RECVMSG,HAS_REMQUO,HAS_RENAME,HAS_RENAMEAT,HAS_RINT,HAS_ROUND,HAS_SCALBNL,HAS_SEM,HAS_SENDMSG,HAS_SETEGID,HAS_SETENV,HAS_SETEUID,HAS_SETGROUPS,HAS_SETHOSTENT,HAS_SETLINEBUF,HAS_SETNETENT,HAS_SETPGRP,HAS_SETPGRP2,HAS_SETPRIORITY,HAS_SETPROCTITLE,HAS_SETPROTOENT,HAS_SETREGID,HAS_SETRESGID,HAS_SETRESUID,HAS_SETREUID,HAS_SETRGID,HAS_SETRUID,HAS_SETSERVENT,HAS_SETSID,HAS_SHM,HAS_SIGACTION,HAS_SIGPROCMASK,HAS_SIN6_SCOPE_ID,HAS_SNPRINTF,HAS_STAT,HAS_STRCOLL,HAS_STRERROR_L,HAS_STRLCAT,HAS_STRLCPY,HAS_STRNLEN,HAS_STRTOD,HAS_STRTOL,HAS_STRTOLL,HAS_STRTOQ,HAS_STRTOUL,HAS_STRTOULL,HAS_STRTOUQ,HAS_STRXFRM,HAS_STRXFRM_L,HAS_SYMLINK,HAS_SYSCALL,HAS_SYSCONF,HAS_SYS_ERRLIST,HAS_SYSTEM,HAS_TCGETPGRP,HAS_TCSETPGRP,HAS_TOWLOWER,HAS_TOWUPPER,HAS_TRUNCATE,HAS_TRUNCL,HAS_UALARM,HAS_UMASK,HAS_UNLINKAT,HAS_UNSETENV,HAS_VFORK,HAS_VSNPRINTF,HAS_WAITPID,HAS_WAIT4,HAS_WCRTOMB,HAS_WCSCMP,HAS_WCSTOMBS,HAS_WCSXFRM,HAS_WCTOMB,HAS_WRITEV
And, the reentrant capabilities:
HAS_CRYPT_R,HAS_CTERMID_R,HAS_DRAND48_R,HAS_ENDHOSTENT_R,HAS_ENDNETENT_R,HAS_ENDPROTOENT_R,HAS_ENDSERVENT_R,HAS_GETGRGID_R,HAS_GETGRNAM_R,HAS_GETHOSTBYADDR_R,HAS_GETHOSTBYNAME_R,HAS_GETHOSTENT_R,HAS_GETLOGIN_R,HAS_GETNETBYADDR_R,HAS_GETNETBYNAME_R,HAS_GETNETENT_R,HAS_GETPROTOBYNAME_R,HAS_GETPROTOBYNUMBER_R,HAS_GETPROTOENT_R,HAS_GETPWNAM_R,HAS_GETPWUID_R,HAS_GETSERVBYNAME_R,HAS_GETSERVBYPORT_R,HAS_GETSERVENT_R,HAS_GETSPNAM_R,HAS_RANDOM_R,HAS_READDIR_R,HAS_SETHOSTENT_R,HAS_SETNETENT_R,HAS_SETPROTOENT_R,HAS_SETSERVENT_R,HAS_SRANDOM_R,HAS_SRAND48_R,HAS_STRERROR_R,HAS_TMPNAM_R,HAS_TTYNAME_R
Example usage:
#ifdef HAS_STRNLEN use strnlen()#else use an alternative implementation#endif#include needed symbolsThis list contains symbols that indicate if certain#include files are present on the platform. If your code accesses the functionality that one of these is for, you will need to#include it if the symbol on this list is#defined. For more detail, see the corresponding entry inconfig.h.
I_ARPA_INET,I_BFD,I_CRYPT,I_DBM,I_DLFCN,I_EXECINFO,I_FP,I_FP_CLASS,I_GDBM,I_GDBMNDBM,I_GDBM_NDBM,I_GRP,I_IEEEFP,I_INTTYPES,I_LIBUTIL,I_MNTENT,I_NDBM,I_NETDB,I_NET_ERRNO,I_NETINET_IN,I_NETINET_TCP,I_PROT,I_PWD,I_RPCSVC_DBM,I_SGTTY,I_SHADOW,I_STDBOOL,I_STDINT,I_SUNMATH,I_SYS_ACCESS,I_SYS_IOCTL,I_SYSLOG,I_SYSMODE,I_SYS_MOUNT,I_SYS_PARAM,I_SYS_POLL,I_SYS_SECURITY,I_SYS_SELECT,I_SYS_STAT,I_SYS_STATVFS,I_SYS_SYSCALL,I_SYS_TIME,I_SYS_TIME_KERNEL,I_SYS_TIMES,I_SYS_TYPES,I_SYSUIO,I_SYS_UN,I_SYSUTSNAME,I_SYS_VFS,I_SYS_WAIT,I_TERMIO,I_TERMIOS,I_UNISTD,I_USTAT,I_VFORK,I_WCHAR,I_WCTYPE
Example usage:
#ifdef I_WCHAR #include <wchar.h>#endifThese variables are global to an entire process. They are shared between all interpreters and all threads in a process. Any variables not documented here may be changed or removed without notice, so don't use them! If you feel you really do need to use an unlisted variable, first send email toperl5-porters@perl.org. It may be that someone there will point out a way to accomplish what you need without using an internal variable. But if not, you should get a go-ahead to document and then use the variable.
PL_checkArray, indexed by opcode, of functions that will be called for the "check" phase of optree building during compilation of Perl code. For most (but not all) types of op, once the op has been initially built and populated with child ops it will be filtered through the check function referenced by the appropriate element of this array. The new op is passed in as the sole argument to the check function, and the check function returns the completed op. The check function may (as the name suggests) check the op for validity and signal errors. It may also initialise or modify parts of the ops, or perform more radical surgery such as adding or removing child ops, or even throw the op away and return a different op in its place.
This array of function pointers is a convenient place to hook into the compilation process. An XS module can put its own custom check function in place of any of the standard ones, to influence the compilation of a particular type of op. However, a custom check function must never fully replace a standard check function (or even a custom check function from another module). A module modifying checking must insteadwrap the preexisting check function. A custom check function must be selective about when to apply its custom behaviour. In the usual case where it decides not to do anything special with an op, it must chain the preexisting op function. Check functions are thus linked in a chain, with the core's base checker at the end.
For thread safety, modules should not write directly to this array. Instead, use the function"wrap_op_checker".
PL_infix_pluginNOTE:PL_infix_plugin isexperimental and may change or be removed without notice.
NOTE: This API exists entirely for the purpose of making the CPAN moduleXS::Parse::Infix work. It is not expected that additional modules will make use of it; rather, that they should useXS::Parse::Infix to provide parsing of new infix operators.
Function pointer, pointing at a function used to handle extended infix operators. The function should be declared as
int infix_plugin_function(pTHX_ char *opname, STRLEN oplen, struct Perl_custom_infix **infix_ptr)The function is called from the tokenizer whenever a possible infix operator is seen.opname points to the operator name in the parser's input buffer, andoplen gives themaximum number of bytes of it that should be consumed; it is not null-terminated. The function is expected to examine the operator name and possibly other state such as%^H, to determine whether it wants to handle the operator name.
As compared to the single stage ofPL_keyword_plugin, parsing of additional infix operators occurs in three separate stages. This is because of the more complex interactions it has with the parser, to ensure that operator precedence rules work correctly. These stages are co-ordinated by the use of an additional information structure.
If the function wants to handle the infix operator, it must set the variable pointed to byinfix_ptr to the address of a structure that provides this additional information about the subsequent parsing stages. If it does not, it should make a call to the next function in the chain.
This structure has the following definition:
struct Perl_custom_infix { enum Perl_custom_infix_precedence prec; void (*parse)(pTHX_ SV **opdata,struct Perl_custom_infix *); OP *(*build_op)(pTHX_ SV **opdata, OP *lhs, OP *rhs,struct Perl_custom_infix *);};The function must then return an integer giving the number of bytes consumed by the name of this operator. In the case of an operator whose name is composed of identifier characters, this must be equal tooplen. In the case of an operator named by non-identifier characters, this is permitted to be shorter thanoplen, and any additional characters after it will not be claimed by the infix operator but instead will be consumed by the tokenizer and parser as normal.
If the optionalparse function is provided, it is called immediately by the parser to let the operator's definition consume any additional syntax from the source code. This shouldnot be used for normal operand parsing, but it may be useful when implementing things like parametric operators or meta-operators that consume more syntax themselves. This function may use the variable pointed to byopdata to provide an SV containing additional data to be passed into thebuild_op function later on.
The information structure gives the operator precedence level in theprec field. This is used to tell the parser how much of the surrounding syntax before and after should be considered as operands to the operator.
The tokenizer and parser will then continue to operate as normal until enough additional input has been parsed to form both the left- and right-hand side operands to the operator, according to the precedence level. At this point thebuild_op function is called, being passed the left- and right-hand operands as optree fragments. It is expected to combine them into the resulting optree fragment, which it should return.
After thebuild_op function has returned, if the variable pointed to byopdata was set to a non-NULL value, it will then be destroyed by callingSvREFCNT_dec().
For thread safety, modules should not set this variable directly. Instead, use the function"wrap_infix_plugin".
However, that all said, the introductory note above still applies. This variable is provided in core perl only for the benefit of theXS::Parse::Infix module. That module acts as a central registry for infix operators, automatically handling things like deparse support and discovery/reflection, and these abilities only work because it knows all the registered operators. Other modules should not use this interpreter variable directly to implement them because then those central features would no longer work properly.
Furthermore, it is likely that this (experimental) API will be replaced in a future Perl version by a more complete API that fully implements the central registry and other semantics currently provided byXS::Parse::Infix, once the module has had sufficient experimental testing time. This current mechanism exists only as an interim measure to get to that stage.
PL_keyword_pluginNOTE:PL_keyword_plugin isexperimental and may change or be removed without notice.
Function pointer, pointing at a function used to handle extended keywords. The function should be declared as
int keyword_plugin_function(pTHX_ char *keyword_ptr, STRLEN keyword_len, OP **op_ptr)The function is called from the tokeniser, whenever a possible keyword is seen.keyword_ptr points at the word in the parser's input buffer, andkeyword_len gives its length; it is not null-terminated. The function is expected to examine the word, and possibly other state such as%^H, to decide whether it wants to handle it as an extended keyword. If it does not, the function should returnKEYWORD_PLUGIN_DECLINE, and the normal parser process will continue.
If the function wants to handle the keyword, it first must parse anything following the keyword that is part of the syntax introduced by the keyword. See"Lexer interface" for details.
When a keyword is being handled, the plugin function must build a tree ofOP structures, representing the code that was parsed. The root of the tree must be stored in*op_ptr. The function then returns a constant indicating the syntactic role of the construct that it has parsed:KEYWORD_PLUGIN_STMT if it is a complete statement, orKEYWORD_PLUGIN_EXPR if it is an expression. Note that a statement construct cannot be used inside an expression (except viado BLOCK and similar), and an expression is not a complete statement (it requires at least a terminating semicolon).
When a keyword is handled, the plugin function may also have (compile-time) side effects. It may modify%^H, define functions, and so on. Typically, if side effects are the main purpose of a handler, it does not wish to generate any ops to be included in the normal compilation. In this case it is still required to supply an op tree, but it suffices to generate a single null op.
That's how the*PL_keyword_plugin function needs to behave overall. Conventionally, however, one does not completely replace the existing handler function. Instead, take a copy ofPL_keyword_plugin before assigning your own function pointer to it. Your handler function should look for keywords that it is interested in and handle those. Where it is not interested, it should call the saved plugin function, passing on the arguments it received. ThusPL_keyword_plugin actually points at a chain of handler functions, all of which have an opportunity to handle keywords, and only the last function in the chain (built into the Perl core) will normally returnKEYWORD_PLUGIN_DECLINE.
For thread safety, modules should not set this variable directly. Instead, use the function"wrap_keyword_plugin".
PL_phaseA value that indicates the current Perl interpreter's phase. Possible values includePERL_PHASE_CONSTRUCT,PERL_PHASE_START,PERL_PHASE_CHECK,PERL_PHASE_INIT,PERL_PHASE_RUN,PERL_PHASE_END, andPERL_PHASE_DESTRUCT.
For example, the following determines whether the interpreter is in global destruction:
if (PL_phase == PERL_PHASE_DESTRUCT) { // we are in global destruction}PL_phase was introduced in Perl 5.14; in prior perls you can usePL_dirty (boolean) to determine whether the interpreter is in global destruction. (Use ofPL_dirty is discouraged since 5.14.)
enum perl_phase PL_phaseA GV is a structure which corresponds to a Perl typeglob, ie *foo. It is a structure that holds a pointer to a scalar, an array, a hash etc, corresponding to $foo, @foo, %foo.
GVs are usually found as values in stashes (symbol table hashes) where Perl stores its global variables.
Astash is a hash that contains all variables that are defined within a package. See"Stashes and Globs" in perlguts
amagic_callPerform the overloaded (active magic) operation given bymethod.method is one of the values found inoverload.h.
flags affects how the operation is performed, as follows:
AMGf_noleftleft is not to be used in this operation.
AMGf_norightright is not to be used in this operation.
AMGf_unaryThe operation is done only on just one operand.
AMGf_assignThe operation changes one of the operands, e.g., $x += 1
SV * amagic_call(SV *left, SV *right, int method, int dir)amagic_deref_callPerformmethod overloading dereferencing onref, returning the dereferenced result.method must be one of the dereference operations given inoverload.h.
If overloading is inactive onref, returnsref itself.
SV * amagic_deref_call(SV *ref, int method)gv_add_by_typeMake sure there is a slot of typetype in the GVgv.
GV * gv_add_by_type(GV *gv, svtype type)Gv_AMupdateRecalculates overload magic in the package given bystash.
Returns:
destructing is true).int Gv_AMupdate(HV *stash, bool destructing)gv_autoload_pvgv_autoload_pvngv_autoload_svThese each search for anAUTOLOAD method, returning NULL if not found, or else returning a pointer to its GV, while setting the package$AUTOLOAD variable toname (fully qualified). Also, if found and the GV's CV is an XSUB, the CV's PV will be set toname, and its stash will be set to the stash of the GV.
Searching is done inMRO order, as specified in"gv_fetchmeth", beginning withstash if it isn't NULL.
The forms differ only in howname is specified.
Ingv_autoload_pv,namepv is a C language NUL-terminated string.
Ingv_autoload_pvn,name points to the first byte of the name, and an additional parameter,len, specifies its length in bytes. Hence,*name may contain embedded-NUL characters.
Ingv_autoload_sv,*namesv is an SV, and the name is the PV extracted from that using"SvPV". If the SV is marked as being in UTF-8, the extracted PV will also be.
GV * gv_autoload_pv (HV *stash, const char *namepv, U32 flags)GV * gv_autoload_pvn(HV *stash, const char *name, STRLEN len, U32 flags)GV * gv_autoload_sv (HV *stash, SV *namesv, U32 flags)gv_autoload4Equivalent to"gv_autoload_pvn".
GV * gv_autoload4(HV *stash, const char *name, STRLEN len, I32 method)GvAVReturn the AV from the GV.
AV* GvAV(GV* gv)gv_AVaddgv_HVaddgv_IOaddgv_SVaddMake sure there is a slot of the given type (AV, HV, IO, SV) in the GVgv.
GV * gv_AVadd(GV *gv)gv_const_svIfgv is a typeglob whose subroutine entry is a constant sub eligible for inlining, orgv is a placeholder reference that would be promoted to such a typeglob, then returns the value returned by the sub. Otherwise, returnsNULL.
SV * gv_const_sv(GV *gv)GvCVReturn the CV from the GV.
CV* GvCV(GV* gv)gv_efullname3gv_efullname4gv_fullname3gv_fullname4Place the full package name ofgv intosv. Thegv_e* forms return instead the effective package name (see"HvENAME").
Ifprefix is non-NULL, it is considered to be a C language NUL-terminated string, and the stored name will be prefaced with it.
The other difference between the functions is that the*4 forms have an extra parameter,keepmain. Iftrue an initialmain:: in the name is kept; iffalse it is stripped. With the*3 forms, it is always kept.
void gv_efullname3(SV *sv, const GV *gv, const char *prefix)void gv_efullname4(SV *sv, const GV *gv, const char *prefix, bool keepmain)void gv_fullname3 (SV *sv, const GV *gv, const char *prefix)void gv_fullname4 (SV *sv, const GV *gv, const char *prefix, bool keepmain)gv_fetchfilegv_fetchfile_flagsThese return the debugger glob for the file (compiled by Perl) whose name is given by thename parameter.
There are currently exactly two differences between these functions.
Thename parameter togv_fetchfile is a C string, meaning it isNUL-terminated; whereas thename parameter togv_fetchfile_flags is a Perl string, whose length (in bytes) is passed in via thenamelen parameter This means the name may contain embeddedNUL characters.namelen doesn't exist in plaingv_fetchfile).
The other difference is thatgv_fetchfile_flags has an extraflags parameter, which is currently completely ignored, but allows for possible future extensions.
GV * gv_fetchfile (const char *name)GV * gv_fetchfile_flags(const char * const name, const STRLEN len, const U32 flags)gv_fetchmethgv_fetchmeth_pvgv_fetchmeth_pvngv_fetchmeth_svThese each look for a glob with namename, containing a defined subroutine, returning the GV of that glob if found, orNULL if not.
stash is always searched (first), unless it isNULL.
Ifstash is NULL, or was searched but nothing was found in it, and theGV_SUPER bit is set inflags, stashes accessible via@ISA are searched next. Searching is conducted according toMRO order.
Finally, if no matches were found so far, and theGV_NOUNIVERSAL flag inflags is not set,UNIVERSAL:: is searched.
The argumentlevel should be either 0 or -1. If -1, the function will return without any side effects or caching. If 0, the function makes sure there is a glob namedname instash, creating one if necessary. The subroutine slot in the glob will be set to any subroutine found in thestash andSUPER:: search, hence caching anySUPER:: result. Note that subroutines found inUNIVERSAL:: are not cached.
The GV returned from these may be a method cache entry, which is not visible to Perl code. So when callingcall_sv, you should not use the GV directly; instead, you should use the method's CV, which can be obtained from the GV with theGvCV macro.
The only other significant value forflags isSVf_UTF8, indicating thatname is to be treated as being encoded in UTF-8.
Plaingv_fetchmeth lacks aflags parameter, hence always searches instash, thenUNIVERSAL::, andname is never UTF-8. Otherwise it is exactly likegv_fetchmeth_pvn.
The other forms do have aflags parameter, and differ only in how the glob name is specified.
Ingv_fetchmeth_pv,name is a C language NUL-terminated string.
Ingv_fetchmeth_pvn,name points to the first byte of the name, and an additional parameter,len, specifies its length in bytes. Hence, the name may contain embedded-NUL characters.
Ingv_fetchmeth_sv,*name is an SV, and the name is the PV extracted from that, using"SvPV". If the SV is marked as being in UTF-8, the extracted PV will also be.
GV * gv_fetchmeth (HV *stash, const char *name, STRLEN len, I32 level)GV * gv_fetchmeth_pv (HV *stash, const char *name, I32 level, U32 flags)GV * gv_fetchmeth_pvn(HV *stash, const char *name, STRLEN len, I32 level, U32 flags)GV * gv_fetchmeth_sv (HV *stash, SV *namesv, I32 level, U32 flags)gv_fetchmeth_autoloadThis is the old form of"gv_fetchmeth_pvn_autoload", which has no flags parameter.
GV * gv_fetchmeth_autoload(HV *stash, const char *name, STRLEN len, I32 level)gv_fetchmethodGV * gv_fetchmethod(HV *stash, const char *name)gv_fetchmethod_autoloadReturns the glob which contains the subroutine to call to invoke the method on thestash. In fact in the presence of autoloading this may be the glob for "AUTOLOAD". In this case the corresponding variable$AUTOLOAD is already setup.
The third parameter ofgv_fetchmethod_autoload determines whether AUTOLOAD lookup is performed if the given method is not present: non-zero means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD. Callinggv_fetchmethod is equivalent to callinggv_fetchmethod_autoload with a non-zeroautoload parameter.
These functions grant"SUPER" token as a prefix of the method name. Note that if you want to keep the returned glob for a long time, you need to check for it being "AUTOLOAD", since at the later time the call may load a different subroutine due to$AUTOLOAD changing its value. Use the glob created as a side effect to do this.
These functions have the same side-effects asgv_fetchmeth withlevel==0. The warning against passing the GV returned bygv_fetchmeth tocall_sv applies equally to these functions.
GV * gv_fetchmethod_autoload(HV *stash, const char *name, I32 autoload)gv_fetchmeth_pv_autoloadExactly like"gv_fetchmeth_pvn_autoload", but takes a nul-terminated string instead of a string/length pair.
GV * gv_fetchmeth_pv_autoload(HV *stash, const char *name, I32 level, U32 flags)gv_fetchmeth_pvn_autoloadSame asgv_fetchmeth_pvn(), but looks for autoloaded subroutines too. Returns a glob for the subroutine.
For an autoloaded subroutine without a GV, will create a GV even iflevel < 0. For an autoloaded subroutine without a stub,GvCV() of the result may be zero.
Currently, the only significant value forflags isSVf_UTF8.
GV * gv_fetchmeth_pvn_autoload(HV *stash, const char *name, STRLEN len, I32 level, U32 flags)gv_fetchmeth_sv_autoloadExactly like"gv_fetchmeth_pvn_autoload", but takes the name string in the form of an SV instead of a string/length pair.
GV * gv_fetchmeth_sv_autoload(HV *stash, SV *namesv, I32 level, U32 flags)gv_fetchpvgv_fetchpvngv_fetchpvn_flagsgv_fetchpvsgv_fetchsvgv_fetchsv_nomgThese all return the GV of typesv_type whose name is given by the inputs, or NULL if no GV of that name and type could be found. See"Stashes and Globs" in perlguts.
The only differences are how the input name is specified, and if 'get' magic is normally used in getting that name.
Don't be fooled by the fact that only one form hasflags in its name. They all have aflags parameter in fact, and all the flag bits have the same meanings for all
If any of the flagsGV_ADD,GV_ADDMG,GV_ADDWARN,GV_ADDMULTI, orGV_NOINIT is set, a GV is created if none already exists for the input name and type. However,GV_ADDMG will only do the creation for magical GV's. For all of these flags exceptGV_NOINIT,"gv_init_pvn" is called after the addition.GV_ADDWARN is used when the caller expects that adding won't be necessary because the symbol should already exist; but if not, add it anyway, with a warning that it was unexpectedly absent. TheGV_ADDMULTI flag means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
The flagGV_NOADD_NOINIT causes"gv_init_pvn" not be to called if the GV existed but isn't PVGV.
If theSVf_UTF8 bit is set, the name is treated as being encoded in UTF-8; otherwise the name won't be considered to be UTF-8 in thepv-named forms, and the UTF-8ness of the underlying SVs will be used in thesv forms.
If the flagGV_NOTQUAL is set, the caller warrants that the input name is a plain symbol name, not qualified with a package, otherwise the name is checked for being a qualified one.
Ingv_fetchpv,nambeg is a C string, NUL-terminated with no intermediate NULs.
Ingv_fetchpvs,name is a literal C string, hence is enclosed in double quotes.
gv_fetchpvn andgv_fetchpvn_flags are identical. In these, <nambeg> is a Perl string whose byte length is given byfull_len, and may contain embedded NULs.
Ingv_fetchsv andgv_fetchsv_nomg, the name is extracted from the PV of the inputname SV. The only difference between these two forms is that 'get' magic is normally done onname ingv_fetchsv, and always skipped withgv_fetchsv_nomg. IncludingGV_NO_SVGMAGIC in theflags parameter togv_fetchsv makes it behave identically togv_fetchsv_nomg.
GV * gv_fetchpv (const char *nambeg, I32 flags, const svtype sv_type)GV * gv_fetchpvn (const char * nambeg, STRLEN full_len, I32 flags, const svtype sv_type)GV * gv_fetchpvn_flags(const char *name, STRLEN len, I32 flags, const svtype sv_type)GV * gv_fetchpvs ("name", I32 flags, const svtype sv_type)GV * gv_fetchsv (SV *name, I32 flags, const svtype sv_type)GV * gv_fetchsv_nomg (SV *name, I32 flags, const svtype sv_type)GvHVReturn the HV from the GV.
HV* GvHV(GV* gv)gv_initThe old form ofgv_init_pvn(). It does not work with UTF-8 strings, as it has no flags parameter. If themulti parameter is set, theGV_ADDMULTI flag will be passed togv_init_pvn().
void gv_init(GV *gv, HV *stash, const char *name, STRLEN len, int multi)gv_init_pvSame asgv_init_pvn(), but takes a nul-terminated string for the name instead of separate char * and length parameters.
void gv_init_pv(GV *gv, HV *stash, const char *name, U32 flags)gv_init_pvnConverts a scalar into a typeglob. This is an incoercible typeglob; assigning a reference to it will assign to one of its slots, instead of overwriting it as happens with typeglobs created bySvSetSV. Converting any scalar that isSvOK() may produce unpredictable results and is reserved for perl's internal use.
gv is the scalar to be converted.
stash is the parent stash/package, if any.
name andlen give the name. The name must be unqualified; that is, it must not include the package name. Ifgv is a stash element, it is the caller's responsibility to ensure that the name passed to this function matches the name of the element. If it does not match, perl's internal bookkeeping will get out of sync.
flags can be set toSVf_UTF8 ifname is a UTF-8 string, or the return value of SvUTF8(sv). It can also take theGV_ADDMULTI flag, which means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
void gv_init_pvn(GV *gv, HV *stash, const char *name, STRLEN len, U32 flags)gv_init_svSame asgv_init_pvn(), but takes an SV * for the name instead of separate char * and length parameters.flags is currently unused.
void gv_init_sv(GV *gv, HV *stash, SV *namesv, U32 flags)gv_name_setSet the name for GVgv toname which islen bytes long. Thus it may contain embedded NUL characters.
Ifflags containsSVf_UTF8, the name is treated as being encoded in UTF-8; otherwise not.
void gv_name_set(GV *gv, const char *name, U32 len, U32 flags)gv_stashpvReturns a pointer to the stash for a specified package. Usesstrlen to determine the length ofname, then callsgv_stashpvn().
HV * gv_stashpv(const char *name, I32 flags)gv_stashpvnReturns a pointer to the stash for a specified package. Thenamelen parameter indicates the length of thename, in bytes.flags is passed togv_fetchpvn_flags(), so if set toGV_ADD then the package will be created if it does not already exist. If the package does not exist andflags is 0 (or any other setting that does not create packages) thenNULL is returned.
Flags may be one of:
GV_ADD Create and initialize the package if doesn't already existGV_NOADD_NOINIT Don't create the package,GV_ADDMG GV_ADD iff the GV is magicalGV_NOINIT GV_ADD, but don't initializeGV_NOEXPAND Don't expand SvOK() entries to PVGVSVf_UTF8 The name is in UTF-8The most important of which are probablyGV_ADD andSVf_UTF8.
Note, use ofgv_stashsv instead ofgv_stashpvn where possible is strongly recommended for performance reasons.
HV * gv_stashpvn(const char *name, U32 namelen, I32 flags)gv_stashpvsLikegv_stashpvn, but takes a literal string instead of a string/length pair.
HV* gv_stashpvs("name", I32 create)gv_stashsvReturns a pointer to the stash for a specified package. See"gv_stashpvn".
Note this interface is strongly preferred overgv_stashpvn for performance reasons.
HV * gv_stashsv(SV *sv, I32 flags)GvSVReturn the SV from the GV.
Prior to Perl v5.9.3, this would add a scalar if none existed. Nowadays, use"GvSVn" for that, or compile perl with-DPERL_CREATE_GVSV. Seeperl5100delta.
SV* GvSV(GV* gv)newGVgennewGVgen_flagsCreate a new, guaranteed to be unique, GV in the package given by the NUL-terminated C language stringpack, and return a pointer to it.
FornewGVgen or ifflags innewGVgen_flags is 0,pack is to be considered to be encoded in Latin-1. The only other legalflags value isSVf_UTF8, which indicatespack is to be considered to be encoded in UTF-8.
GV * newGVgen (const char *pack)GV * newGVgen_flags(const char *pack, U32 flags)PL_curstashThe stash for the package code will be compiled into.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
HV* PL_curstashPL_defgvThe GV representing*_. Useful for access to$_.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
GV * PL_defgvPL_defoutgvSee"setdefout".
save_gpSaves the current GP of gv on the save stack to be restored on scope exit.
Ifempty is true, replace the GP with a new GP.
Ifempty is false, markgv withGVf_INTRO so the next reference assigned is localized, which is how local *foo = $someref; works.
void save_gp(GV *gv, I32 empty)setdefoutSetsPL_defoutgv, the default file handle for output, to the passed in typeglob. AsPL_defoutgv "owns" a reference on its typeglob, the reference count of the passed in typeglob is increased by one, and the reference count of the typeglob thatPL_defoutgv points to is decreased by one.
void setdefout(GV *gv)These functions provide convenient and thread-safe means of manipulating hook variables.
rcpv_copyrefcount increment a shared memory refcounted string, and when the refcount goes to 0 free it using PerlMemShared_free().
It is the callers responsibility to ensure that the pv is the result of a rcpv_new() call.
Returns the same pointer that was passed in.
new = rcpv_copy(pv);char * rcpv_copy(char * const pv)rcpv_freerefcount decrement a shared memory refcounted string, and when the refcount goes to 0 free it using perlmemshared_free().
it is the callers responsibility to ensure that the pv is the result of a rcpv_new() call.
Always returns NULL so it can be used like this:
thing = rcpv_free(thing);char * rcpv_free(char * const pv)rcpv_newCreate a new shared memory refcounted string with the requested size, and with the requested initialization and a refcount of 1. The actual space allocated will be 1 byte more than requested and rcpv_new() will ensure that the extra byte is a null regardless of any flags settings.
If the RCPVf_NO_COPY flag is set then the pv argument will be ignored, otherwise the contents of the pv pointer will be copied into the new buffer or if it is NULL the function will do nothing and return NULL.
If the RCPVf_USE_STRLEN flag is set then the len argument is ignored and recomputed usingstrlen(pv). It is an error to combine RCPVf_USE_STRLEN and RCPVf_NO_COPY at the same time.
Under DEBUGGING rcpv_new() will assert() if it is asked to create a 0 length shared string unless the RCPVf_ALLOW_EMPTY flag is set.
The return value from the function is suitable for passing into rcpv_copy() and rcpv_free(). To access the RCPV * from the returned value use the RCPVx() macro. The 'len' member of the RCPV struct stores the allocated length (including the extra byte), but the RCPV_LEN() macro returns the requested length (not including the extra byte).
Note that rcpv_new() does NOT use a hash table or anything like that to dedupe inputs given the same text content. Each call with a non-null pv parameter will produce a distinct pointer with its own refcount regardless of the input content.
char * rcpv_new(const char * const pv, STRLEN len, U32 flags)wrap_op_checkerPuts a C function into the chain of check functions for a specified op type. This is the preferred way to manipulate the"PL_check" array.opcode specifies which type of op is to be affected.new_checker is a pointer to the C function that is to be added to that opcode's check chain, andold_checker_p points to the storage location where a pointer to the next function in the chain will be stored. The value ofnew_checker is written into the"PL_check" array, while the value previously stored there is written to*old_checker_p.
"PL_check" is global to an entire process, and a module wishing to hook op checking may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location*old_checker_p must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also markedstatic to give it internal linkage) will be implicitly initialised appropriately, if it does not have an explicit initialiser. This function will only actually modify the check chain if it finds*old_checker_p to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing"PL_check".
When this function is called, the function referenced bynew_checker must be ready to be called, except for*old_checker_p being unfilled. In a threading situation,new_checker may be called immediately, even before this function has returned.*old_checker_p will always be appropriately set beforenew_checker is called. Ifnew_checker decides not to do anything special with an op that it is given (which is the usual case for most uses of op check hooking), it must chain the check function referenced by*old_checker_p.
Taken all together, XS code to hook an op checker should typically look something like this:
static Perl_check_t nxck_frob;static OP *myck_frob(pTHX_ OP *op) { ... op = nxck_frob(aTHX_ op); ... return op;}BOOT: wrap_op_checker(OP_FROB, myck_frob, &nxck_frob);If you want to influence compilation of calls to a specific subroutine, then use"cv_set_call_checker_flags" rather than hooking checking of allentersub ops.
void wrap_op_checker(Optype opcode, Perl_check_t new_checker, Perl_check_t *old_checker_p)A HV structure represents a Perl hash. It consists mainly of an array of pointers, each of which points to a linked list of HE structures. The array is indexed by the hash function of the key, so each linked list represents all the hash entries with the same hash value. Each HE contains a pointer to the actual value, plus a pointer to a HEK structure which holds the key and hash value.
get_hvReturns the HV of the specified Perl hash.flags are passed togv_fetchpv. IfGV_ADD is set and the Perl variable does not exist then it will be created. Ifflags is zero (ignoringSVf_UTF8) and the variable does not exist thenNULL is returned.
NOTE: theperl_get_hv() form isdeprecated.
HV * get_hv(const char *name, I32 flags)HEf_SVKEYThis flag, used in the length slot of hash entries and magic structures, specifies the structure contains anSV* pointer where achar* pointer is to be expected. (For information only--not to be used).
HeHASHReturns the computed hash stored in the hash entry.
U32 HeHASH(HE* he)HeKEYReturns the actual pointer stored in the key slot of the hash entry. The pointer may be eitherchar* orSV*, depending on the value ofHeKLEN(). Can be assigned to. TheHePV() orHeSVKEY() macros are usually preferable for finding the value of a key.
void* HeKEY(HE* he)HeKLENIf this is negative, and amounts toHEf_SVKEY, it indicates the entry holds anSV* key. Otherwise, holds the actual length of the key. Can be assigned to. TheHePV() macro is usually preferable for finding key lengths.
STRLEN HeKLEN(HE* he)HePVReturns the key slot of the hash entry as achar* value, doing any necessary dereferencing of possiblySV* keys. The length of the string is placed inlen (this is a macro, so donot use&len). If you do not care about what the length of the key is, you may use the global variablePL_na, though this is rather less efficient than using a local variable. Remember though, that hash keys in perl are free to contain embedded nulls, so usingstrlen() or similar is not a good way to find the length of hash keys. This is very similar to theSvPV() macro described elsewhere in this document. See also"HeUTF8".
If you are usingHePV to get values to pass tonewSVpvn() to create a new SV, you should consider usingnewSVhek(HeKEY_hek(he)) as it is more efficient.
char* HePV(HE* he, STRLEN len)HeSVKEYReturns the key as anSV*, orNULL if the hash entry does not contain anSV* key.
SV* HeSVKEY(HE* he)HeSVKEY_forceReturns the key as anSV*. Will create and return a temporary mortalSV* if the hash entry contains only achar* key.
SV* HeSVKEY_force(HE* he)HeSVKEY_setSets the key to a givenSV*, taking care to set the appropriate flags to indicate the presence of anSV* key, and returns the sameSV*.
SV* HeSVKEY_set(HE* he, SV* sv)HeUTF8Returns whether thechar * value returned byHePV is encoded in UTF-8, doing any necessary dereferencing of possiblySV* keys. The value returned will be 0 or non-0, not necessarily 1 (or even a value with any low bits set), sodo not blindly assign this to abool variable, asbool may be a typedef forchar.
U32 HeUTF8(HE* he)HeVALReturns the value slot (typeSV*) stored in the hash entry. Can be assigned to.
SV *foo= HeVAL(hv);HeVAL(hv)= sv;SV* HeVAL(HE* he)hv_assertCheck that a hash is in an internally consistent state.
NOTE:hv_assert must be explicitly called asPerl_hv_assert with anaTHX_ parameter.
void Perl_hv_assert(pTHX_ HV *hv)hv_bucket_ratioNOTE:hv_bucket_ratio isexperimental and may change or be removed without notice.
If the hash is tied dispatches through to the SCALAR tied method, otherwise if the hash contains no keys returns 0, otherwise returns a mortal sv containing a string specifying the number of used buckets, followed by a slash, followed by the number of available buckets.
This function is expensive, it must scan all of the buckets to determine which are used, and the count is NOT cached. In a large hash this could be a lot of buckets.
SV * hv_bucket_ratio(HV *hv)hv_clearFrees all the elements of a hash, leaving it empty. The XS equivalent of%hash = (). See also"hv_undef".
See"av_clear" for a note about the hash possibly being invalid on return.
void hv_clear(HV *hv)hv_clear_placeholdersClears any placeholders from a hash. If a restricted hash has any of its keys marked as readonly and the key is subsequently deleted, the key is not actually deleted but is marked by assigning it a value of&PL_sv_placeholder. This tags it so it will be ignored by future operations such as iterating over the hash, but will still allow the hash to have a value reassigned to the key at some future point. This function clears any such placeholder keys from the hash. SeeHash::Util::lock_keys() for an example of its use.
void hv_clear_placeholders(HV *hv)hv_copy_hints_hvA specialised version of"newHVhv" for copying%^H.ohv must be a pointer to a hash (which may have%^H magic, but should be generally non-magical), orNULL (interpreted as an empty hash). The content ofohv is copied to a new hash, which has the%^H-specific magic added to it. A pointer to the new hash is returned.
HV * hv_copy_hints_hv(HV * const ohv)hv_deletehv_deletesThese delete a key/value pair in the hash. The value's SV is removed from the hash, made mortal, and returned to the caller.
Inhv_deletes, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
Inhv_delete, the absolute value ofklen is the length of the key. Ifklen is negative the key is assumed to be in UTF-8-encoded Unicode.
In both, theflags value will normally be zero; if set toG_DISCARD thenNULL will be returned.NULL will also be returned if the key is not found.
SV * hv_delete (HV *hv, const char *key, I32 klen, I32 flags)SV * hv_deletes(HV *hv, "key", U32 flags)hv_delete_entDeletes a key/value pair in the hash. The value SV is removed from the hash, made mortal, and returned to the caller. Theflags value will normally be zero; if set toG_DISCARD thenNULL will be returned.NULL will also be returned if the key is not found.hash can be a valid precomputed hash value, or 0 to ask for it to be computed.
SV * hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)HvENAMEReturns the effective name of a stash, or NULL if there is none. The effective name represents a location in the symbol table where this stash resides. It is updated automatically when packages are aliased or deleted. A stash that is no longer in the symbol table has no effective name. This name is preferable toHvNAME for use in MRO linearisations and isa caches.
char* HvENAME(HV* stash)HvENAMELENReturns the length of the stash's effective name.
STRLEN HvENAMELEN(HV *stash)HvENAMEUTF8Returns true if the effective name is in UTF-8 encoding.
unsigned char HvENAMEUTF8(HV *stash)hv_existshv_existssThese return a boolean indicating whether the specified hash key exists.
Inhv_existss, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
Inhv_exists, the absolute value ofklen is the length of the key. Ifklen is negative the key is assumed to be in UTF-8-encoded Unicode.
bool hv_exists (HV *hv, const char *key, I32 klen)bool hv_existss(HV *hv, "key")hv_exists_entReturns a boolean indicating whether the specified hash key exists.hash can be a valid precomputed hash value, or 0 to ask for it to be computed.
bool hv_exists_ent(HV *hv, SV *keysv, U32 hash)hv_fetchhv_fetchsThese return the SV which corresponds to the specified key in the hash.
Inhv_fetchs, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
Inhv_fetch, the absolute value ofklen is the length of the key. Ifklen is negative the key is assumed to be in UTF-8-encoded Unicode.
In both, iflval is set, then the fetch will be part of a store. This means that if there is no value in the hash associated with the given key, then one is created and a pointer to it is returned. TheSV* it points to can be assigned to. But always check that the return value is non-null before dereferencing it to anSV*.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
SV ** hv_fetch (HV *hv, const char *key, I32 klen, I32 lval)SV ** hv_fetchs(HV *hv, "key", I32 lval)hv_fetch_entReturns the hash entry which corresponds to the specified key in the hash.hash must be a valid precomputed hash number for the givenkey, or 0 if you want the function to compute it. IFlval is set then the fetch will be part of a store. Make sure the return value is non-null before accessing it. The return value whenhv is a tied hash is a pointer to a static location, so be sure to make a copy of the structure if you need to store it somewhere.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
HE * hv_fetch_ent(HV *hv, SV *keysv, I32 lval, U32 hash)hv_fetchsLikehv_fetch, but takes a literal string instead of a string/length pair.
SV** hv_fetchs(HV* tb, "key", I32 lval)HvFILLReturns the number of hash buckets that happen to be in use.
As of perl 5.25 this function is used only for debugging purposes, and the number of used hash buckets is not in any way cached, thus this function can be costly to execute as it must iterate over all the buckets in the hash.
STRLEN HvFILL(HV *const hv)HvHasAUXReturns true if the HV has astruct xpvhv_aux extension. Use this to check whether it is valid to callHvAUX().
bool HvHasAUX(HV *const hv)hv_iterinitPrepares a starting point to traverse a hash table. Returns the number of keys in the hash, including placeholders (i.e. the same asHvTOTALKEYS(hv)). The return value is currently only meaningful for hashes without tie magic.
NOTE: Before version 5.004_65,hv_iterinit used to return the number of hash buckets that happen to be in use. If you still need that esoteric value, you can get it through the macroHvFILL(hv).
I32 hv_iterinit(HV *hv)hv_iterkeyReturns the key from the current position of the hash iterator. See"hv_iterinit".
char * hv_iterkey(HE *entry, I32 *retlen)hv_iterkeysvReturns the key as anSV* from the current position of the hash iterator. The return value will always be a mortal copy of the key. Also see"hv_iterinit".
SV * hv_iterkeysv(HE *entry)hv_iternextReturns entries from a hash iterator. See"hv_iterinit".
You may callhv_delete orhv_delete_ent on the hash entry that the iterator currently points to, without losing your place or invalidating your iterator. Note that in this case the current entry is deleted from the hash with your iterator holding the last reference to it. Your iterator is flagged to free the entry on the next call tohv_iternext, so you must not discard your iterator immediately else the entry will leak - callhv_iternext to trigger the resource deallocation.
HE * hv_iternext(HV *hv)hv_iternext_flagsNOTE:hv_iternext_flags isexperimental and may change or be removed without notice.
Returns entries from a hash iterator. See"hv_iterinit" and"hv_iternext". Theflags value will normally be zero; ifHV_ITERNEXT_WANTPLACEHOLDERS is set the placeholders keys (for restricted hashes) will be returned in addition to normal keys. By default placeholders are automatically skipped over. Currently a placeholder is implemented with a value that is&PL_sv_placeholder. Note that the implementation of placeholders and restricted hashes may change, and the implementation currently is insufficiently abstracted for any change to be tidy.
HE * hv_iternext_flags(HV *hv, I32 flags)hv_iternextsvPerforms anhv_iternext,hv_iterkey, andhv_iterval in one operation.
SV * hv_iternextsv(HV *hv, char **key, I32 *retlen)hv_itervalReturns the value from the current position of the hash iterator. See"hv_iterkey".
SV * hv_iterval(HV *hv, HE *entry)hv_ksplitAttempt to grow the hashhv so it has at leastnewmax buckets available. Perl chooses the actual number for its convenience.
This is the same as doing the following in Perl code:
keys %hv = newmax;void hv_ksplit(HV *hv, IV newmax)hv_magicAdds magic to a hash. See"sv_magic".
void hv_magic(HV *hv, GV *gv, int how)HvNAMEReturns the package name of a stash, orNULL ifstash isn't a stash. See"SvSTASH","CvSTASH".
char* HvNAME(HV* stash)HvNAMELENReturns the length of the stash's name.
Disfavored forms of HvNAME and HvNAMELEN; suppress mention of them
STRLEN HvNAMELEN(HV *stash)hv_name_sethv_name_setsThese each set the name of stashhv to the specified name.
They differ only in how the name is specified.
Inhv_name_sets, the name is a literal C string, enclosed in double quotes.
Inhv_name_set,name points to the first byte of the name, and an additional parameter,len, specifies its length in bytes. Hence, the name may contain embedded-NUL characters.
IfSVf_UTF8 is set inflags, the name is treated as being in UTF-8; otherwise not.
IfHV_NAME_SETALL is set inflags, both the name and the effective name are set.
void hv_name_set (HV *hv, const char *name, U32 len, U32 flags)void hv_name_sets(HV *hv, "name", U32 flags)HvNAMEUTF8Returns true if the name is in UTF-8 encoding.
unsigned char HvNAMEUTF8(HV *stash)hv_scalarEvaluates the hash in scalar context and returns the result.
When the hash is tied dispatches through to the SCALAR method, otherwise returns a mortal SV containing the number of keys in the hash.
Note, prior to 5.25 this function returned what is now returned by the hv_bucket_ratio() function.
SV * hv_scalar(HV *hv)hv_storehv_storesThese each store SVval with the specified key in hashhv, returning NULL if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise it can be dereferenced to get the originalSV*.
They differ only in how the hash key is specified.
Inhv_stores, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
Inhv_store,key is either NULL or points to the first byte of the string specifying the key, and its length in bytes is given by the absolute value of an additional parameter,klen. A NULL key indicates the key is to be treated asundef, andklen is ignored; otherwise the key string may contain embedded-NUL bytes. Ifklen is negative, the string is treated as being encoded in UTF-8; otherwise not.
hv_store has another extra parameter,hash, a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted fromhv_stores, as it is computed automatically at compile time.
If <hv> is NULL, NULL is returned and no action is taken.
Ifval is NULL, it is treated as beingundef; otherwise the caller is responsible for suitably incrementing the reference count ofval before the call, and decrementing it if the function returnedNULL. Effectively a successfulhv_store takes ownership of one reference toval. This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash,hv_store will own the only reference to the new SV, and your code doesn't need to do anything further to tidy up.
hv_store is not implemented as a call to"hv_store_ent", and does not create a temporary SV for the key, so if your key data is not already in SV form then usehv_store in preference tohv_store_ent.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
SV ** hv_store (HV *hv, const char *key, I32 klen, SV *val, U32 hash)SV ** hv_stores(HV *hv, "key", SV *val)hv_store_entStoresval in a hash. The hash key is specified askey. Thehash parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value is the new hash entry so created. It will beNULL if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise the contents of the return value can be accessed using theHe? macros described here. Note that the caller is responsible for suitably incrementing the reference count ofval before the call, and decrementing it if the function returned NULL. Effectively a successfulhv_store_ent takes ownership of one reference toval. This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash,hv_store will own the only reference to the new SV, and your code doesn't need to do anything further to tidy up. Note thathv_store_ent only reads thekey; unlikeval it does not take ownership of it, so maintaining the correct reference count onkey is entirely the caller's responsibility. The reason it does not take ownership, is thatkey is not used after this function returns, and so can be freed immediately.hv_store is not implemented as a call tohv_store_ent, and does not create a temporary SV for the key, so if your key data is not already in SV form then usehv_store in preference tohv_store_ent.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
HE * hv_store_ent(HV *hv, SV *key, SV *val, U32 hash)hv_undefUndefines the hash. The XS equivalent ofundef(%hash).
As well as freeing all the elements of the hash (likehv_clear()), this also frees any auxiliary data and storage associated with the hash.
See"av_clear" for a note about the hash possibly being invalid on return.
void hv_undef(HV *hv)newHVCreates a new HV. The reference count is set to 1.
HV * newHV()newHVhvThe content ofohv is copied to a new hash. A pointer to the new hash is returned.
HV * newHVhv(HV *hv)NullhvDEPRECATED! It is planned to removeNullhv from a future release of Perl. Do not use it for new code; remove it from existing code.
Null HV pointer.
(deprecated - use(HV *)NULL instead)
PL_modglobalPL_modglobal is a general purpose, interpreter global HV for use by extensions that need to keep information on a per-interpreter basis. In a pinch, it can also be used as a symbol table for extensions to share data among each other. It is a good idea to use keys prefixed by the package name of the extension that owns the data.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
HV* PL_modglobaldo_closeClose an I/O stream. This implements Perl"close" in perlfunc.
gv is the glob associated with the stream.
is_explict istrue if this is an explicit close of the stream;false if it is part of another operation, such as closing a pipe (which involves implicitly closing both ends).
Returnstrue if successful; otherwise returnsfalse and setserrno to indicate the cause.
bool do_close(GV *gv, bool is_explicit)my_chsizeThe C librarychsize(3) if available, or a Perl implementation of it.
I32 my_chsize(int fd, Off_t length)my_dirfdThe C librarydirfd(3) if available, or a Perl implementation of it, or die if not easily emulatable.
int my_dirfd(DIR *dir)my_pcloseA wrapper for the C librarypclose(3). Don't use the latter, as the Perl version knows things that interact with the rest of the perl interpreter.
I32 my_pclose(PerlIO *ptr)my_popenA wrapper for the C librarypopen(3). Don't use the latter, as the Perl version knows things that interact with the rest of the perl interpreter.
PerlIO * my_popen(const char *cmd, const char *mode)newIOCreate a new IO, setting the reference count to 1.
IO * newIO()PERL_FLUSHALL_FOR_CHILDThis defines a way to flush all output buffers. This may be a performance issue, so we allow people to disable it. Also, if we are using stdio, there are broken implementations of fflush(NULL) out there, Solaris being the most prominent.
void PERL_FLUSHALL_FOR_CHILDPerlIO_apply_layersPerlIO_binmodePerlIO_canset_cntPerlIO_clearerrPerlIO_closePerlIO_debugPerlIO_eofPerlIO_errorPerlIO_exportFILEPerlIO_fast_getsPerlIO_fdopenPerlIO_filenoPerlIO_fillPerlIO_findFILEPerlIO_flushPerlIO_get_basePerlIO_get_bufsizPerlIO_get_cntPerlIO_get_ptrPerlIO_getcPerlIO_getposPerlIO_has_basePerlIO_has_cntptrPerlIO_importFILEPerlIO_openPerlIO_printfPerlIO_putcPerlIO_putsPerlIO_readPerlIO_releaseFILEPerlIO_reopenPerlIO_rewindPerlIO_seekPerlIO_set_cntPerlIO_set_ptrcntPerlIO_setlinebufPerlIO_setposPerlIO_stderrPerlIO_stdinPerlIO_stdoutPerlIO_stdoutfPerlIO_tellPerlIO_ungetcPerlIO_unreadPerlIO_vprintfPerlIO_writeDescribed inperlapio.
int PerlIO_apply_layers(PerlIO *f, const char *mode, const char *layers)int PerlIO_binmode (PerlIO *f, int ptype, int imode, const char *layers)int PerlIO_canset_cnt (PerlIO *f)void PerlIO_clearerr (PerlIO *f)int PerlIO_close (PerlIO *f)void PerlIO_debug (const char *fmt, ...)int PerlIO_eof (PerlIO *f)int PerlIO_error (PerlIO *f)FILE * PerlIO_exportFILE (PerlIO *f, const char *mode)int PerlIO_fast_gets (PerlIO *f)PerlIO * PerlIO_fdopen (int fd, const char *mode)int PerlIO_fileno (PerlIO *f)int PerlIO_fill (PerlIO *f)FILE * PerlIO_findFILE (PerlIO *f)int PerlIO_flush (PerlIO *f)STDCHAR * PerlIO_get_base (PerlIO *f)SSize_t PerlIO_get_bufsiz (PerlIO *f)SSize_t PerlIO_get_cnt (PerlIO *f)STDCHAR * PerlIO_get_ptr (PerlIO *f)int PerlIO_getc (PerlIO *d)int PerlIO_getpos (PerlIO *f, SV *save)int PerlIO_has_base (PerlIO *f)int PerlIO_has_cntptr (PerlIO *f)PerlIO * PerlIO_importFILE (FILE *stdio, const char *mode)PerlIO * PerlIO_open (const char *path, const char *mode)int PerlIO_printf (PerlIO *f, const char *fmt, ...)int PerlIO_putc (PerlIO *f, int ch)int PerlIO_puts (PerlIO *f, const char *string)SSize_t PerlIO_read (PerlIO *f, void *vbuf, Size_t count)void PerlIO_releaseFILE (PerlIO *f, FILE *stdio)PerlIO * PerlIO_reopen (const char *path, const char *mode, PerlIO *old)void PerlIO_rewind (PerlIO *f)int PerlIO_seek (PerlIO *f, Off_t offset, int whence)void PerlIO_set_cnt (PerlIO *f, SSize_t cnt)void PerlIO_set_ptrcnt (PerlIO *f, STDCHAR *ptr, SSize_t cnt)void PerlIO_setlinebuf (PerlIO *f)int PerlIO_setpos (PerlIO *f, SV *saved)PerlIO * PerlIO_stderr (PerlIO *f, const char *mode, const char *layers)PerlIO * PerlIO_stdin (PerlIO *f, const char *mode, const char *layers)PerlIO * PerlIO_stdout (PerlIO *f, const char *mode, const char *layers)int PerlIO_stdoutf (const char *fmt, ...)Off_t PerlIO_tell (PerlIO *f)int PerlIO_ungetc (PerlIO *f, int ch)SSize_t PerlIO_unread (PerlIO *f, const void *vbuf, Size_t count)int PerlIO_vprintf (PerlIO *f, const char *fmt, va_list args)SSize_t PerlIO_write (PerlIO *f, const void *vbuf, Size_t count)PERLIO_F_APPENDPERLIO_F_CANREADPERLIO_F_CANWRITEPERLIO_F_CRLFPERLIO_F_EOFPERLIO_F_ERRORPERLIO_F_FASTGETSPERLIO_F_LINEBUFPERLIO_F_OPENPERLIO_F_RDBUFPERLIO_F_TEMPPERLIO_F_TRUNCATEPERLIO_F_UNBUFPERLIO_F_UTF8PERLIO_F_WRBUFDescribed inperliol.
PERLIO_FUNCS_CASTCast the pointerfunc to be of typePerlIO_funcs *.
PERLIO_FUNCS_DECLDeclareftab to be a PerlIO function table, that is, of typePerlIO_funcs.
PERLIO_FUNCS_DECL(PerlIO * ftab)PERLIO_K_BUFFEREDPERLIO_K_CANCRLFPERLIO_K_FASTGETSPERLIO_K_MULTIARGPERLIO_K_RAWDescribed inperliol.
repeatcpyMakecount copies of thelen bytes beginning atfrom, placing them into memory beginning atto, which must be big enough to accommodate them all.
void repeatcpy(char *to, const char *from, SSize_t len, IV count)CASTI32This symbol is defined if the C compiler can cast negative or large floating point numbers to 32-bit ints.
HAS_INT64_TThis symbol will defined if the C compiler supportsint64_t. Usually theinttypes.h needs to be included, but sometimessys/types.h is enough.
HAS_LONG_LONGThis symbol will be defined if the C compiler supports long long.
HAS_QUADThis symbol, if defined, tells that there's a 64-bit integer type,Quad_t, and its unsigned counterpart,Uquad_t.QUADKIND will be one ofQUAD_IS_INT,QUAD_IS_LONG,QUAD_IS_LONG_LONG,QUAD_IS_INT64_T, orQUAD_IS___INT64.
I32dfThis symbol defines the format string used for printing a Perl I32 as a signed decimal integer.
INT16_CINT32_CINT64_CReturns a token the C compiler recognizes for the constantnumber of the corresponding integer type on the machine.
If the machine does not have a 64-bit type,INT64_C is undefined. Use"INTMAX_C" to get the largest type available on the platform.
I16 INT16_C(number)I32 INT32_C(number)I64 INT64_C(number)INTMAX_CReturns a token the C compiler recognizes for the constantnumber of the widest integer type on the machine. For example, if the machine haslong longs,INTMAX_C(-1) would yield
-1LLSee also, for example,"INT32_C".
Use"IV" to declare variables of the maximum usable size on this platform.
INTMAX_C(number)INTSIZEThis symbol contains the value ofsizeof(int) so that the C preprocessor can make decisions based on it.
I8SIZEThis symbol contains thesizeof(I8).
I16SIZEThis symbol contains thesizeof(I16).
I32SIZEThis symbol contains thesizeof(I32).
I64SIZEThis symbol contains thesizeof(I64).
I8TYPEThis symbol defines the C type used for Perl's I8.
I16TYPEThis symbol defines the C type used for Perl's I16.
I32TYPEThis symbol defines the C type used for Perl's I32.
I64TYPEThis symbol defines the C type used for Perl's I64.
IV_MAXThe largest signed integer that fits in an IV on this platform.
IV IV_MAXIV_MINThe negative signed integer furthest away from 0 that fits in an IV on this platform.
IV IV_MINIVSIZEThis symbol contains thesizeof(IV).
IVTYPEThis symbol defines the C type used for Perl's IV.
line_tThe typedef to use to declare variables that are to hold line numbers.
LONGLONGSIZEThis symbol contains the size of a long long, so that the C preprocessor can make decisions based on it. It is only defined if the system supports long long.
LONGSIZEThis symbol contains the value ofsizeof(long) so that the C preprocessor can make decisions based on it.
memzeroSet thel bytes starting at*d to all zeroes.
void memzero(void * d, Size_t l)PERL_INT_FAST8_TPERL_INT_FAST16_TPERL_UINT_FAST8_TPERL_UINT_FAST16_TThese are equivalent to the correspondingly-named C99 typedefs on platforms that have those; they evaluate toint andunsigned int on platforms that don't, so that you can portably take advantage of this C99 feature.
PERL_INT_MAXPERL_INT_MINPERL_LONG_MAXPERL_LONG_MINPERL_QUAD_MAXPERL_QUAD_MINPERL_SHORT_MAXPERL_SHORT_MINPERL_UCHAR_MAXPERL_UCHAR_MINPERL_UINT_MAXPERL_UINT_MINPERL_ULONG_MAXPERL_ULONG_MINPERL_UQUAD_MAXPERL_UQUAD_MINPERL_USHORT_MAXPERL_USHORT_MINThese give the largest and smallest number representable in the current platform in variables of the corresponding types.
For signed types, the smallest representable number is the most negative number, the one furthest away from zero.
For C99 and later compilers, these correspond to things likeINT_MAX, which are available to the C code. But these constants, furnished by Perl, allow code compiled on earlier compilers to portably have access to the same constants.
int PERL_INT_MAXint PERL_INT_MINlong PERL_LONG_MAXlong PERL_LONG_MINIV PERL_QUAD_MAXIV PERL_QUAD_MINshort PERL_SHORT_MAXshort PERL_SHORT_MINU8 PERL_UCHAR_MAXU8 PERL_UCHAR_MINunsigned int PERL_UINT_MAXunsigned int PERL_UINT_MINunsigned long PERL_ULONG_MAXunsigned long PERL_ULONG_MINUV PERL_UQUAD_MAXUV PERL_UQUAD_MINunsigned short PERL_USHORT_MAXunsigned short PERL_USHORT_MINSHORTSIZEThis symbol contains the value ofsizeof(short) so that the C preprocessor can make decisions based on it.
UINT16_CUINT32_CUINT64_CReturns a token the C compiler recognizes for the constantnumber of the corresponding unsigned integer type on the machine.
If the machine does not have a 64-bit type,UINT64_C is undefined. Use"UINTMAX_C" to get the largest type available on the platform.
U16 UINT16_C(number)U32 UINT32_C(number)U64 UINT64_C(number)UINTMAX_CReturns a token the C compiler recognizes for the constantnumber of the widest unsigned integer type on the machine. For example, if the machine haslongs,UINTMAX_C(1) would yield
1ULSee also, for example,"UINT32_C".
Use"UV" to declare variables of the maximum usable size on this platform.
UINTMAX_C(number)U32ofThis symbol defines the format string used for printing a Perl U32 as an unsigned octal integer.
U8SIZEThis symbol contains thesizeof(U8).
U16SIZEThis symbol contains thesizeof(U16).
U32SIZEThis symbol contains thesizeof(U32).
U64SIZEThis symbol contains thesizeof(U64).
U8TYPEThis symbol defines the C type used for Perl's U8.
U16TYPEThis symbol defines the C type used for Perl's U16.
U32TYPEThis symbol defines the C type used for Perl's U32.
U64TYPEThis symbol defines the C type used for Perl's U64.
U32ufThis symbol defines the format string used for printing a Perl U32 as an unsigned decimal integer.
UV_MAXThe largest unsigned integer that fits in a UV on this platform.
UV UV_MAXUV_MINThe smallest unsigned integer that fits in a UV on this platform. It should equal zero.
UV UV_MINUVSIZEThis symbol contains thesizeof(UV).
UVTYPEThis symbol defines the C type used for Perl's UV.
U32XfThis symbol defines the format string used for printing a Perl U32 as an unsigned hexadecimal integer in uppercaseABCDEF.
U32xfThis symbol defines the format string used for printing a Perl U32 as an unsigned hexadecimal integer in lowercase abcdef.
WIDEST_UTYPEYields the widest unsigned integer type on the platform, currently eitherU32 orU64. This can be used in declarations such as
WIDEST_UTYPE my_uv;or casts
my_uv = (WIDEST_UTYPE) val;These are used for formatting the corresponding type For example, instead of saying
Perl_newSVpvf(pTHX_ "Create an SV with a %d in it\n", iv);use
Perl_newSVpvf(pTHX_ "Create an SV with a " IVdf " in it\n", iv);This keeps you from having to know if, say an IV, needs to be printed as%d,%ld, or something else.
IVdfThis symbol defines the format string used for printing a Perl IV as a signed decimal integer.
NVefThis symbol defines the format string used for printing a Perl NV using %e-ish floating point format.
NVffThis symbol defines the format string used for printing a Perl NV using %f-ish floating point format.
NVgfThis symbol defines the format string used for printing a Perl NV using %g-ish floating point format.
PERL_PRIeldblThis symbol, if defined, contains the string used by stdio to format long doubles (format 'e') for output.
PERL_PRIfldblThis symbol, if defined, contains the string used by stdio to format long doubles (format 'f') for output.
PERL_PRIgldblThis symbol, if defined, contains the string used by stdio to format long doubles (format 'g') for output.
PERL_SCNfldblThis symbol, if defined, contains the string used by stdio to format long doubles (format 'f') for input.
PRINTF_FORMAT_NULL_OKAllows__printf__ format to be null when checking printf-style
UVfDEPRECATED! It is planned to removeUVf from a future release of Perl. Do not use it for new code; remove it from existing code.
Obsolete form ofUVuf, which you should convert to instead use
const char * UVfUVofThis symbol defines the format string used for printing a Perl UV as an unsigned octal integer.
UVufThis symbol defines the format string used for printing a Perl UV as an unsigned decimal integer.
UVXfThis symbol defines the format string used for printing a Perl UV as an unsigned hexadecimal integer in uppercaseABCDEF.
UVxfThis symbol defines the format string used for printing a Perl UV as an unsigned hexadecimal integer in lowercase abcdef.
This is the lower layer of the Perl parser, managing characters and tokens.
lex_bufutf8NOTE:lex_bufutf8 isexperimental and may change or be removed without notice.
Indicates whether the octets in the lexer buffer ("PL_parser->linestr") should be interpreted as the UTF-8 encoding of Unicode characters. If not, they should be interpreted as Latin-1 characters. This is analogous to theSvUTF8 flag for scalars.
In UTF-8 mode, it is not guaranteed that the lexer buffer actually contains valid UTF-8. Lexing code must be robust in the face of invalid encoding.
The actualSvUTF8 flag of the"PL_parser->linestr" scalar is significant, but not the whole story regarding the input character encoding. Normally, when a file is being read, the scalar contains octets and itsSvUTF8 flag is off, but the octets should be interpreted as UTF-8 if theuse utf8 pragma is in effect. During a string eval, however, the scalar may have theSvUTF8 flag on, and in this case its octets should be interpreted as UTF-8 unless theuse bytes pragma is in effect. This logic may change in the future; use this function instead of implementing the logic yourself.
bool lex_bufutf8()lex_discard_toNOTE:lex_discard_to isexperimental and may change or be removed without notice.
Discards the first part of the"PL_parser->linestr" buffer, up toptr. The remaining content of the buffer will be moved, and all pointers into the buffer updated appropriately.ptr must not be later in the buffer than the position of"PL_parser->bufptr": it is not permitted to discard text that has yet to be lexed.
Normally it is not necessarily to do this directly, because it suffices to use the implicit discarding behaviour of"lex_next_chunk" and things based on it. However, if a token stretches across multiple lines, and the lexing code has kept multiple lines of text in the buffer for that purpose, then after completion of the token it would be wise to explicitly discard the now-unneeded earlier lines, to avoid future multi-line tokens growing the buffer without bound.
void lex_discard_to(char *ptr)lex_grow_linestrNOTE:lex_grow_linestr isexperimental and may change or be removed without notice.
Reallocates the lexer buffer ("PL_parser->linestr") to accommodate at leastlen octets (including terminatingNUL). Returns a pointer to the reallocated buffer. This is necessary before making any direct modification of the buffer that would increase its length."lex_stuff_pvn" provides a more convenient way to insert text into the buffer.
Do not useSvGROW orsv_grow directly onPL_parser->linestr; this function updates all of the lexer's variables that point directly into the buffer.
char * lex_grow_linestr(STRLEN len)lex_next_chunkNOTE:lex_next_chunk isexperimental and may change or be removed without notice.
Reads in the next chunk of text to be lexed, appending it to"PL_parser->linestr". This should be called when lexing code has looked to the end of the current chunk and wants to know more. It is usual, but not necessary, for lexing to have consumed the entirety of the current chunk at this time.
If"PL_parser->bufptr" is pointing to the very end of the current chunk (i.e., the current chunk has been entirely consumed), normally the current chunk will be discarded at the same time that the new chunk is read in. Ifflags has theLEX_KEEP_PREVIOUS bit set, the current chunk will not be discarded. If the current chunk has not been entirely consumed, then it will not be discarded regardless of the flag.
Returns true if some new text was added to the buffer, or false if the buffer has reached the end of the input text.
bool lex_next_chunk(U32 flags)lex_peek_unicharNOTE:lex_peek_unichar isexperimental and may change or be removed without notice.
Looks ahead one (Unicode) character in the text currently being lexed. Returns the codepoint (unsigned integer value) of the next character, or -1 if lexing has reached the end of the input text. To consume the peeked character, use"lex_read_unichar".
If the next character is in (or extends into) the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but ifflags has theLEX_KEEP_PREVIOUS bit set, then the current chunk will not be discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding error is encountered, an exception is generated.
I32 lex_peek_unichar(U32 flags)lex_read_spaceNOTE:lex_read_space isexperimental and may change or be removed without notice.
Reads optional spaces, in Perl style, in the text currently being lexed. The spaces may include ordinary whitespace characters and Perl-style comments.#line directives are processed if encountered."PL_parser->bufptr" is moved past the spaces, so that it points at a non-space character (or the end of the input text).
If spaces extend into the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but ifflags has theLEX_KEEP_PREVIOUS bit set, then the current chunk will not be discarded.
void lex_read_space(U32 flags)lex_read_toNOTE:lex_read_to isexperimental and may change or be removed without notice.
Consume text in the lexer buffer, from"PL_parser->bufptr" up toptr. This advances"PL_parser->bufptr" to matchptr, performing the correct bookkeeping whenever a newline character is passed. This is the normal way to consume lexed text.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level functions"lex_peek_unichar" and"lex_read_unichar".
void lex_read_to(char *ptr)lex_read_unicharNOTE:lex_read_unichar isexperimental and may change or be removed without notice.
Reads the next (Unicode) character in the text currently being lexed. Returns the codepoint (unsigned integer value) of the character read, and moves"PL_parser->bufptr" past the character, or returns -1 if lexing has reached the end of the input text. To non-destructively examine the next character, use"lex_peek_unichar" instead.
If the next character is in (or extends into) the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but ifflags has theLEX_KEEP_PREVIOUS bit set, then the current chunk will not be discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding error is encountered, an exception is generated.
I32 lex_read_unichar(U32 flags)lex_startNOTE:lex_start isexperimental and may change or be removed without notice.
Creates and initialises a new lexer/parser state object, supplying a context in which to lex and parse from a new source of Perl code. A pointer to the new state object is placed in"PL_parser". An entry is made on the save stack so that upon unwinding, the new state object will be destroyed and the former value of"PL_parser" will be restored. Nothing else need be done to clean up the parsing context.
The code to be parsed comes fromline andrsfp.line, if non-null, provides a string (in SV form) containing code to be parsed. A copy of the string is made, so subsequent modification ofline does not affect parsing.rsfp, if non-null, provides an input stream from which code will be read to be parsed. If both are non-null, the code inline comes first and must consist of complete lines of input, andrsfp supplies the remainder of the source.
Theflags parameter is reserved for future use. Currently it is only used by perl internally, so extensions should always pass zero.
void lex_start(SV *line, PerlIO *rsfp, U32 flags)lex_stuff_pvNOTE:lex_stuff_pv isexperimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by octets starting atpv and continuing to the first nul. These octets are interpreted as either UTF-8 or Latin-1, according to whether theLEX_STUFF_UTF8 flag is set inflags. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If it is not convenient to nul-terminate a string to be inserted, the"lex_stuff_pvn" function is more appropriate.
void lex_stuff_pv(const char *pv, U32 flags)lex_stuff_pvnNOTE:lex_stuff_pvn isexperimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented bylen octets starting atpv. These octets are interpreted as either UTF-8 or Latin-1, according to whether theLEX_STUFF_UTF8 flag is set inflags. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string to be inserted is available as a Perl scalar, the"lex_stuff_sv" function is more convenient.
void lex_stuff_pvn(const char *pv, STRLEN len, U32 flags)lex_stuff_pvsNOTE:lex_stuff_pvs isexperimental and may change or be removed without notice.
Like"lex_stuff_pvn", but takes a literal string instead of a string/length pair.
void lex_stuff_pvs("pv", U32 flags)lex_stuff_svNOTE:lex_stuff_sv isexperimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is the string value ofsv. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string to be inserted is not already a Perl scalar, the"lex_stuff_pvn" function avoids the need to construct a scalar.
void lex_stuff_sv(SV *sv, U32 flags)lex_unstuffNOTE:lex_unstuff isexperimental and may change or be removed without notice.
Discards text about to be lexed, from"PL_parser->bufptr" up toptr. Text followingptr will be moved, and the buffer shortened. This hides the discarded text from any lexing code that runs later, as if the text had never appeared.
This is not the normal way to consume lexed text. For that, use"lex_read_to".
void lex_unstuff(char *ptr)parse_arithexprNOTE:parse_arithexpr isexperimental and may change or be removed without notice.
Parse a Perl arithmetic expression. This may contain operators of precedence down to the bit shift operators. The expression must be followed (and thus terminated) either by a comparison or lower-precedence operator or by something that would normally terminate an expression such as semicolon. Ifflags has thePARSE_OPTIONAL bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_arithexpr(U32 flags)parse_barestmtNOTE:parse_barestmt isexperimental and may change or be removed without notice.
Parse a single unadorned Perl statement. This may be a normal imperative statement or a declaration that has compile-time effect. It does not include any label or other affixture. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement is null, for example if it was actually a subroutine definition (which has compile-time side effects). If not null, it will be ops directly implementing the statement, suitable to pass to"newSTATEOP". It will not normally include anextstate or equivalent op (except for those embedded in a scope contained entirely within the statement).
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
Theflags parameter is reserved for future use, and must always be zero.
OP * parse_barestmt(U32 flags)parse_blockNOTE:parse_block isexperimental and may change or be removed without notice.
Parse a single complete Perl code block. This consists of an opening brace, a sequence of statements, and a closing brace. The block constitutes a lexical scope, somy variables and various compile-time effects can be contained within it. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the code block is returned. This is always a real op, never a null pointer. It will normally be alineseq list, includingnextstate or equivalent ops. No ops to construct any kind of runtime scope are included by virtue of it being a block.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
Theflags parameter is reserved for future use, and must always be zero.
OP * parse_block(U32 flags)parse_fullexprNOTE:parse_fullexpr isexperimental and may change or be removed without notice.
Parse a single complete Perl expression. This allows the full expression grammar, including the lowest-precedence operators such asor. The expression must be followed (and thus terminated) by a token that an expression would normally be terminated by: end-of-file, closing bracketing punctuation, semicolon, or one of the keywords that signals a postfix expression-statement modifier. Ifflags has thePARSE_OPTIONAL bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_fullexpr(U32 flags)parse_fullstmtNOTE:parse_fullstmt isexperimental and may change or be removed without notice.
Parse a single complete Perl statement. This may be a normal imperative statement or a declaration that has compile-time effect, and may include optional labels. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement is null, for example if it was actually a subroutine definition (which has compile-time side effects). If not null, it will be the result of a"newSTATEOP" call, normally including anextstate or equivalent op.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
Theflags parameter is reserved for future use, and must always be zero.
OP * parse_fullstmt(U32 flags)parse_labelNOTE:parse_label isexperimental and may change or be removed without notice.
Parse a single label, possibly optional, of the type that may prefix a Perl statement. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed. Ifflags has thePARSE_OPTIONAL bit set, then the label is optional, otherwise it is mandatory.
The name of the label is returned in the form of a fresh scalar. If an optional label is absent, a null pointer is returned.
If an error occurs in parsing, which can only occur if the label is mandatory, a valid label is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred.
SV * parse_label(U32 flags)parse_listexprNOTE:parse_listexpr isexperimental and may change or be removed without notice.
Parse a Perl list expression. This may contain operators of precedence down to the comma operator. The expression must be followed (and thus terminated) either by a low-precedence logic operator such asor or by something that would normally terminate an expression such as semicolon. Ifflags has thePARSE_OPTIONAL bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_listexpr(U32 flags)parse_stmtseqNOTE:parse_stmtseq isexperimental and may change or be removed without notice.
Parse a sequence of zero or more Perl statements. These may be normal imperative statements, including optional labels, or declarations that have compile-time effect, or any mixture thereof. The statement sequence ends when a closing brace or end-of-file is encountered in a place where a new statement could have validly started. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statements.
The op tree representing the statement sequence is returned. This may be a null pointer if the statements were all null, for example if there were no statements or if there were only subroutine definitions (which have compile-time side effects). If not null, it will be alineseq list, normally includingnextstate or equivalent ops.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
Theflags parameter is reserved for future use, and must always be zero.
OP * parse_stmtseq(U32 flags)parse_subsignatureNOTE:parse_subsignature isexperimental and may change or be removed without notice.
Parse a subroutine signature declaration. This is the contents of the parentheses following a named or anonymous subroutine declaration when thesignatures feature is enabled. Note that this function neither expects nor consumes the opening and closing parentheses around the signature; it is the caller's job to handle these.
This function must only be called during parsing of a subroutine; after"start_subparse" has been called. It might allocate lexical variables on the pad for the current subroutine.
The op tree to unpack the arguments from the stack at runtime is returned. This op tree should appear at the beginning of the compiled function. The caller may wish to use"op_append_list" to build their function body after it, or splice it together with the body before calling"newATTRSUB".
Theflags parameter is reserved for future use, and must always be zero.
OP * parse_subsignature(U32 flags)parse_termexprNOTE:parse_termexpr isexperimental and may change or be removed without notice.
Parse a Perl term expression. This may contain operators of precedence down to the assignment operators. The expression must be followed (and thus terminated) either by a comma or lower-precedence operator or by something that would normally terminate an expression such as semicolon. Ifflags has thePARSE_OPTIONAL bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_termexpr(U32 flags)PL_parserPointer to a structure encapsulating the state of the parsing operation currently in progress. The pointer can be locally changed to perform a nested parse without interfering with the state of an outer parse. Individual members ofPL_parser have their own documentation.
PL_parser->bufendNOTE:PL_parser->bufend isexperimental and may change or be removed without notice.
Direct pointer to the end of the chunk of text currently being lexed, the end of the lexer buffer. This is equal toSvPVX(PL_parser->linestr) + SvCUR(PL_parser->linestr). ANUL character (zero octet) is always located at the end of the buffer, and does not count as part of the buffer's contents.
PL_parser->bufptrNOTE:PL_parser->bufptr isexperimental and may change or be removed without notice.
Points to the current position of lexing inside the lexer buffer. Characters around this point may be freely examined, within the range delimited bySvPVX("PL_parser->linestr") and"PL_parser->bufend". The octets of the buffer may be intended to be interpreted as either UTF-8 or Latin-1, as indicated by"lex_bufutf8".
Lexing code (whether in the Perl core or not) moves this pointer past the characters that it consumes. It is also expected to perform some bookkeeping whenever a newline character is consumed. This movement can be more conveniently performed by the function"lex_read_to", which handles newlines appropriately.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level functions"lex_peek_unichar" and"lex_read_unichar".
PL_parser->linestartNOTE:PL_parser->linestart isexperimental and may change or be removed without notice.
Points to the start of the current line inside the lexer buffer. This is useful for indicating at which column an error occurred, and not much else. This must be updated by any lexing code that consumes a newline; the function"lex_read_to" handles this detail.
PL_parser->linestrNOTE:PL_parser->linestr isexperimental and may change or be removed without notice.
Buffer scalar containing the chunk currently under consideration of the text currently being lexed. This is always a plain string scalar (for whichSvPOK is true). It is not intended to be used as a scalar by normal scalar means; instead refer to the buffer directly by the pointer variables described below.
The lexer maintains variouschar* pointers to things in thePL_parser->linestr buffer. IfPL_parser->linestr is ever reallocated, all of these pointers must be updated. Don't attempt to do this manually, but rather use"lex_grow_linestr" if you need to reallocate the buffer.
The content of the text chunk in the buffer is commonly exactly one complete line of input, up to and including a newline terminator, but there are situations where it is otherwise. The octets of the buffer may be intended to be interpreted as either UTF-8 or Latin-1. The function"lex_bufutf8" tells you which. Do not use theSvUTF8 flag on this scalar, which may disagree with it.
For direct examination of the buffer, the variable"PL_parser->bufend" points to the end of the buffer. The current lexing position is pointed to by"PL_parser->bufptr". Direct use of these pointers is usually preferable to examination of the scalar through normal scalar means.
suspend_compcvImplements part of the concept of a "suspended compilation CV", which can be used to pause the parser and compiler during parsing a CV in order to come back to it later on.
This function saves the current state of the subroutine under compilation (PL_compcv) into the supplied buffer. This should be used initially to create the state in the buffer, as the final thing before aLEAVE within a block.
ENTER;start_subparse(0);...suspend_compcv(&buffer);LEAVE;Once suspended, theresume_compcv_final orresume_compcv_and_save function can later be used to continue the parsing from the point this stopped.
void suspend_compcv(struct suspended_compcv *buffer)wrap_infix_pluginNOTE:wrap_infix_plugin isexperimental and may change or be removed without notice.
NOTE: This API exists entirely for the purpose of making the CPAN moduleXS::Parse::Infix work. It is not expected that additional modules will make use of it; rather, that they should useXS::Parse::Infix to provide parsing of new infix operators.
Puts a C function into the chain of infix plugins. This is the preferred way to manipulate the"PL_infix_plugin" variable.new_plugin is a pointer to the C function that is to be added to the infix plugin chain, andold_plugin_p points to a storage location where a pointer to the next function in the chain will be stored. The value ofnew_plugin is written into the"PL_infix_plugin" variable, while the value previously stored there is written to*old_plugin_p.
Direct access to"PL_infix_plugin" should be avoided.
void wrap_infix_plugin(Perl_infix_plugin_t new_plugin, Perl_infix_plugin_t *old_plugin_p)wrap_keyword_pluginNOTE:wrap_keyword_plugin isexperimental and may change or be removed without notice.
Puts a C function into the chain of keyword plugins. This is the preferred way to manipulate the"PL_keyword_plugin" variable.new_plugin is a pointer to the C function that is to be added to the keyword plugin chain, andold_plugin_p points to the storage location where a pointer to the next function in the chain will be stored. The value ofnew_plugin is written into the"PL_keyword_plugin" variable, while the value previously stored there is written to*old_plugin_p.
"PL_keyword_plugin" is global to an entire process, and a module wishing to hook keyword parsing may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location*old_plugin_p must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also markedstatic to give it internal linkage) will be implicitly initialised appropriately, if it does not have an explicit initialiser. This function will only actually modify the plugin chain if it finds*old_plugin_p to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing"PL_keyword_plugin".
When this function is called, the function referenced bynew_plugin must be ready to be called, except for*old_plugin_p being unfilled. In a threading situation,new_plugin may be called immediately, even before this function has returned.*old_plugin_p will always be appropriately set beforenew_plugin is called. Ifnew_plugin decides not to do anything special with the identifier that it is given (which is the usual case for most calls to a keyword plugin), it must chain the plugin function referenced by*old_plugin_p.
Taken all together, XS code to install a keyword plugin should typically look something like this:
static Perl_keyword_plugin_t next_keyword_plugin;static OP *my_keyword_plugin(pTHX_ char *keyword_ptr, STRLEN keyword_len, OP **op_ptr){ if (memEQs(keyword_ptr, keyword_len, "my_new_keyword")) { ... } else { return next_keyword_plugin(aTHX_ keyword_ptr, keyword_len, op_ptr); }}BOOT: wrap_keyword_plugin(my_keyword_plugin, &next_keyword_plugin);Direct access to"PL_keyword_plugin" should be avoided.
void wrap_keyword_plugin(Perl_keyword_plugin_t new_plugin, Perl_keyword_plugin_t *old_plugin_p)DECLARATION_FOR_LC_NUMERIC_MANIPULATIONThis macro should be used as a statement. It declares a private variable (whose name begins with an underscore) that is needed by the other macros in this section. Failing to include this correctly should lead to a syntax error. For compatibility with C89 C compilers it should be placed in a block before any executable statements.
void DECLARATION_FOR_LC_NUMERIC_MANIPULATIONfoldEQ_localeReturns true if the leadinglen bytes of the stringss1 ands2 are the same case-insensitively in the current locale; false otherwise.
I32 foldEQ_locale(const char *a, const char *b, I32 len)HAS_DUPLOCALEThis symbol, if defined, indicates that theduplocale routine is available to duplicate a locale object.
HAS_FREELOCALEThis symbol, if defined, indicates that thefreelocale routine is available to deallocates the resources associated with a locale object.
HAS_LC_MONETARY_2008This symbol, if defined, indicates that the localeconv routine is available and has the additional members added inPOSIX 1003.1-2008.
HAS_LOCALECONVThis symbol, if defined, indicates that thelocaleconv routine is available for numeric and monetary formatting conventions.
HAS_LOCALECONV_LThis symbol, if defined, indicates that thelocaleconv_l routine is available to query certain information about a locale.
HAS_NEWLOCALEThis symbol, if defined, indicates that thenewlocale routine is available to return a new locale object or modify an existing locale object.
HAS_NL_LANGINFOThis symbol, if defined, indicates that thenl_langinfo routine is available to return locale data. You will also needlanginfo.h and thereforeI_LANGINFO.
HAS_NL_LANGINFO_LThis symbol, if defined, indicates that thenl_langinfo_l routine is available to return locale data. You will also needlanginfo.h and thereforeI_LANGINFO.
HAS_QUERYLOCALEThis symbol, if defined, indicates that thequerylocale routine is available to return the name of the locale for a category mask.
HAS_SETLOCALEThis symbol, if defined, indicates that thesetlocale routine is available to handle locale-specific ctype implementations.
HAS_SETLOCALE_RThis symbol, if defined, indicates that thesetlocale_r routine is available to setlocale re-entrantly.
HAS_USELOCALEThis symbol, if defined, indicates that theuselocale routine is available to set the current locale for the calling thread.
I_LANGINFOThis symbol, if defined, indicates thatlanginfo.h exists and should be included.
#ifdef I_LANGINFO #include <langinfo.h>#endifI_LOCALEThis symbol, if defined, indicates to the C program that it should includelocale.h.
#ifdef I_LOCALE #include <locale.h>#endifIN_LOCALEEvaluates to TRUE if the plain locale pragma without a parameter (use locale) is in effect.
bool IN_LOCALEIN_LOCALE_COMPILETIMEEvaluates to TRUE if, when compiling a perl program (including aneval) if the plain locale pragma without a parameter (use locale) is in effect.
bool IN_LOCALE_COMPILETIMEIN_LOCALE_RUNTIMEEvaluates to TRUE if, when executing a perl program (including aneval) if the plain locale pragma without a parameter (use locale) is in effect.
bool IN_LOCALE_RUNTIMEI_XLOCALEThis symbol, if defined, indicates to the C program that the headerxlocale.h is available. See also"NEED_XLOCALE_H"
#ifdef I_XLOCALE #include <xlocale.h>#endifNEED_XLOCALE_HThis symbol, if defined, indicates that the C program should includexlocale.h to getnewlocale() and its friends.
Perl_langinfoPerl_langinfo8Perl_langinfo is an (almost) drop-in replacement for the systemnl_langinfo(3), taking the sameitem parameter values, and returning the same information. But it is more thread-safe than regularnl_langinfo(), and hides the quirks of Perl's locale handling from your code, and can be used on systems that lack a nativenl_langinfo.
However, you should instead use either the improved version of this,"Perl_langinfo8", or even better,"sv_langinfo". The latter returns an SV, handling all the possible non-standard returns ofnl_langinfo(), including the UTF8ness of any returned string.
Perl_langinfo8 is identical toPerl_langinfo except for an additional parameter, a pointer to a variable declared as"utf8ness_t", into which it returns to you how you should treat the returned string with regards to it being encoded in UTF-8 or not.
These two functions share private per-thread memory that will be changed the next time either one of them is called with any input, but not before.
Concerning the differences between these and plainnl_langinfo():
Perl_langinfo8 has an extra parameter, described above. Besides this, the other reason they aren't quite a drop-in replacement is actually an advantage. Theconstness of the return allows the compiler to catch attempts to write into the returned buffer, which is illegal and could cause run-time crashes.
They deliver the correct results for theRADIXCHAR andTHOUSEP items, without you having to write extra code. The reason for the extra code would be because these are from theLC_NUMERIC locale category, which is normally kept set by Perl so that the radix is a dot, and the separator is the empty string, no matter what the underlying locale is supposed to be, and so to get the expected results, you have to temporarily toggle into the underlying locale, and later toggle back. (You could use plainnl_langinfo and"STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" for this but then you wouldn't get the other advantages ofPerl_langinfo(); not keepingLC_NUMERIC in the C (or equivalent) locale would break a lot of CPAN, which is expecting the radix (decimal point) character to be a dot.)
The system function they replace can have its static return buffer trashed, not only by a subsequent call to that function, but by afreelocale,setlocale, or other locale change. The returned buffer of these functions is not changed until the next call to one or the other, so the buffer is never in a trashed state.
The return buffer is per-thread, so it also is never overwritten by a call to these functions from another thread; unlike the function it replaces.
But most importantly, they work on systems that don't havenl_langinfo, such as Windows, hence making your code more portable. Of the fifty-some possible items specified by the POSIX 2008 standard,https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html, only one is completely unimplemented, though on non-Windows platforms, another significant one is not fully implemented). They use various techniques to recover the other items, including callinglocaleconv(3), andstrftime(3), both of which are specified in C89, so should be always be available. Laterstrftime() versions have additional capabilities. If an item is not available on your system, this returns either the value associated with the C locale, or simply"", whichever is more appropriate.
It is important to note that, when called with an item that is recovered by usinglocaleconv, the buffer from any previous explicit call tolocaleconv(3) will be overwritten. But you shouldn't be usinglocaleconv anyway because it is is very much not thread-safe, and suffers from the same problems outlined in item 'b.' above for the fields it returns that are controlled by the LC_NUMERIC locale category. Instead, avoid all of those problems by calling"Perl_localeconv", which is thread-safe; or by using the methods given inperlcall to callPOSIX::localeconv(), which is also thread-safe.
The details for those items which may deviate from what this emulation returns and what a nativenl_langinfo() would return are specified inI18N::Langinfo.
const char * Perl_langinfo (const nl_item item)const char * Perl_langinfo8(const nl_item item, utf8ness_t *utf8ness)PERL_LC_ALL_CATEGORY_POSITIONS_INITThis symbol, when defined, gives the C initializer for an array whose element [0] is the first category in the string returned bysetlocale(LC_ALL, NULL) when not all categories are the same, on systems that use a positional notation. After element [0] isLC_ALL_SEPARATOR, then the category given by element [1] and so on.
PERL_LC_ALL_SEPARATORThis symbol, if defined, gives the string returned bysetlocale(LC_ALL, NULL) to separate categories that are in different locales on systems that use a positional notation as opposed to 'name=value' pairs. An example on some platforms could be the '/' in "C/de_DE/C/en_UK/C/C"
PERL_LC_ALL_USES_NAME_VALUE_PAIRSThis symbol, if defined, indicates to the C program that the string returned bysetlocale(LC_ALL, NULL) uses 'name=value;' pairs to indicate what each category's locale is when they aren't all set to the same locale. For example, "LC_NUMERIC=C;LC_CTYPE=de_DE;..." When not defined, the system uses positional notation.
Perl_localeconvThis is a thread-safe version of the libclocaleconv(3). It is the same asPOSIX::localeconv (returning a hash of thelocaleconv() fields), but directly callable from XS code. The hash is mortalized, so must be dealt with immediately.
HV * Perl_localeconv(pTHX)Perl_setlocaleThis is an (almost) drop-in replacement for the systemsetlocale(3), taking the same parameters, and returning the same information, except that it returns the correct underlyingLC_NUMERIC locale. Regularsetlocale will instead returnC if the underlying locale has a non-dot decimal point character, or a non-empty thousands separator for displaying floating point numbers. This is because perl keeps that locale category such that it has a dot and empty separator, changing the locale briefly during the operations where the underlying one is required.Perl_setlocale knows about this, and compensates; regularsetlocale doesn't.
Another reason it isn't completely a drop-in replacement is that it is declared to returnconst char *, whereas the system setlocale omits theconst (presumably because its API was specified long ago, and can't be updated; it is illegal to change the informationsetlocale returns; doing so leads to segfaults.)
Finally,Perl_setlocale works under all circumstances, whereas plainsetlocale can be completely ineffective on some platforms under some configurations.
Changing the locale is not a good idea when more than one thread is running, except on systems where the predefined variable${^SAFE_LOCALES} is non-zero. This is because on such systems the locale is global to the whole process and not local to just the thread calling the function. So changing it in one thread instantaneously changes it in all. On some such systems, the systemsetlocale() is ineffective, returning the wrong information, and failing to actually change the locale. z/OS refuses to try to change the locale once a second thread is created.Perl_setlocale, should give you accurate results of what actually happened on these problematic platforms, returning NULL if the system forbade the locale change.
The return points to a per-thread static buffer, which is overwritten the next timePerl_setlocale is called from the same thread.
const char * Perl_setlocale(const int category, const char *locale)RESTORE_LC_NUMERICThis is used in conjunction with one of the macros"STORE_LC_NUMERIC_SET_TO_NEEDED" and"STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" to properly restore theLC_NUMERIC state.
A call to"DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro and the twoSTORE ones. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{ DECLARATION_FOR_LC_NUMERIC_MANIPULATION; ... RESTORE_LC_NUMERIC(); ...}void RESTORE_LC_NUMERIC()SETLOCALE_ACCEPTS_ANY_LOCALE_NAMEThis symbol, if defined, indicates that the setlocale routine is available and it accepts any input locale name as valid.
STORE_LC_NUMERIC_FORCE_TO_UNDERLYINGThis is used by XS code that isLC_NUMERIC locale-aware to force the locale for categoryLC_NUMERIC to be what perl thinks is the current underlying locale. (The perl interpreter could be wrong about what the underlying locale actually is if some C or XS code has called the C library functionsetlocale(3) behind its back; calling"sync_locale" before calling this macro will update perl's records.)
A call to"DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{ DECLARATION_FOR_LC_NUMERIC_MANIPULATION; ... STORE_LC_NUMERIC_FORCE_TO_UNDERLYING(); ... RESTORE_LC_NUMERIC(); ...}The private variable is used to save the current locale state, so that the requisite matching call to"RESTORE_LC_NUMERIC" can restore it.
On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called.
void STORE_LC_NUMERIC_FORCE_TO_UNDERLYING()STORE_LC_NUMERIC_SET_TO_NEEDEDThis is used to help wrap XS or C code that isLC_NUMERIC locale-aware. This locale category is generally kept set to a locale where the decimal radix character is a dot, and the separator between groups of digits is empty. This is because most XS code that reads floating point numbers is expecting them to have this syntax.
This macro makes sure the currentLC_NUMERIC state is set properly, to be aware of locale if the call to the XS or C code from the Perl program is from within the scope of ause locale; or to ignore locale if the call is instead from outside such scope.
This macro is the start of wrapping the C or XS code; the wrap ending is done by calling the"RESTORE_LC_NUMERIC" macro after the operation. Otherwise the state can be changed that will adversely affect other XS code.
A call to"DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{ DECLARATION_FOR_LC_NUMERIC_MANIPULATION; ... STORE_LC_NUMERIC_SET_TO_NEEDED(); ... RESTORE_LC_NUMERIC(); ...}On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called; see"WITH_LC_NUMERIC_SET_TO_NEEDED" for a more contained way to ensure that.
void STORE_LC_NUMERIC_SET_TO_NEEDED()STORE_LC_NUMERIC_SET_TO_NEEDED_INSame as"STORE_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided as the precalculated value ofIN_LC(LC_NUMERIC). It is the caller's responsibility to ensure that the status ofPL_compiling andPL_hints cannot have changed since the precalculation.
void STORE_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric)sv_langinfoThis is the preferred interface for accessing the data thatnl_langinfo(3) provides (or Perl's emulation of it on platforms lacking it), returning an SV. Unlike, the earlier-defined interfaces to this ("Perl_langinfo" and"Perl_langinfo8"), which return strings, the UTF8ness of the result is automatically handled for you. And like them, it is thread-safe and automatically handles getting the proper values for theRADIXCHAR andTHOUSEP items (that calling the plain libcnl_langinfo() could give the wrong results for). Like them, this also doesn't play well with the libclocaleconv(); usePOSIX::localeconv() instead.
There are a few deviations from what a nativenl_langinfo() would return and what this returns on platforms that don't implement that function. These are detailed inI18N::Langinfo.
SV * sv_langinfo(const nl_item item)WITH_LC_NUMERIC_SET_TO_NEEDEDThis macro invokes the supplied statement or block within the context of a"STORE_LC_NUMERIC_SET_TO_NEEDED" .."RESTORE_LC_NUMERIC" pair if required, so eg:
WITH_LC_NUMERIC_SET_TO_NEEDED( SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis));is equivalent to:
{#ifdef USE_LOCALE_NUMERIC DECLARATION_FOR_LC_NUMERIC_MANIPULATION; STORE_LC_NUMERIC_SET_TO_NEEDED();#endif SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis);#ifdef USE_LOCALE_NUMERIC RESTORE_LC_NUMERIC();#endif}void WITH_LC_NUMERIC_SET_TO_NEEDED(block)WITH_LC_NUMERIC_SET_TO_NEEDED_INSame as"WITH_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided as the precalculated value ofIN_LC(LC_NUMERIC). It is the caller's responsibility to ensure that the status ofPL_compiling andPL_hints cannot have changed since the precalculation.
void WITH_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric, block)"Magic" is special data attached to SV structures in order to give them "magical" properties. When any Perl code tries to read from, or assign to, an SV marked as magical, it calls the 'get' or 'set' function associated with that SV's magic. A get is called prior to reading an SV, in order to give it a chance to update its internal value (get on $. writes the line number of the last read filehandle into the SV's IV slot), while set is called after an SV has been written to, in order to allow it to make use of its changed value (set on $/ copies the SV's new value to the PL_rs global variable).
Magic is implemented as a linked list of MAGIC structures attached to the SV. Each MAGIC struct holds the type of the magic, a pointer to an array of functions that implement the get(), set(), length() etc functions, plus space for some flags and pointers. For example, a tied variable has a MAGIC structure that contains a pointer to the object associated with the tie.
mg_clearClear something magical that the SV represents. See"sv_magic".
int mg_clear(SV *sv)mg_copyCopies the magic from one SV to another. See"sv_magic".
int mg_copy(SV *sv, SV *nsv, const char *key, I32 klen)mg_findFinds the magic pointer fortype matching the SV. See"sv_magic".
MAGIC * mg_find(const SV *sv, int type)mg_findextFinds the magic pointer oftype with the givenvtbl for theSV. See"sv_magicext".
MAGIC * mg_findext(const SV *sv, int type, const MGVTBL *vtbl)mg_freeFree any magic storage used by the SV. See"sv_magic".
int mg_free(SV *sv)mg_freeextRemove any magic of typehow using virtual tablevtbl from the SVsv. See"sv_magic".
mg_freeext(sv, how, NULL) is equivalent tomg_free_type(sv, how).
void mg_freeext(SV *sv, int how, const MGVTBL *vtbl)mg_free_typeRemove any magic of typehow from the SVsv. See"sv_magic".
void mg_free_type(SV *sv, int how)mg_getDo magic before a value is retrieved from the SV. The type of SV must be >=SVt_PVMG. See"sv_magic".
int mg_get(SV *sv)mg_magicalTurns on the magical status of an SV. See"sv_magic".
void mg_magical(SV *sv)mg_setDo magic after a value is assigned to the SV. See"sv_magic".
int mg_set(SV *sv)PERL_MAGIC_arylenPERL_MAGIC_arylen_pPERL_MAGIC_backrefPERL_MAGIC_bmPERL_MAGIC_checkcallPERL_MAGIC_collxfrmPERL_MAGIC_dbfilePERL_MAGIC_dblinePERL_MAGIC_debugvarPERL_MAGIC_defelemPERL_MAGIC_destructPERL_MAGIC_envPERL_MAGIC_envelemPERL_MAGIC_extPERL_MAGIC_extvaluePERL_MAGIC_fmPERL_MAGIC_hintsPERL_MAGIC_hintselemPERL_MAGIC_hookPERL_MAGIC_hookelemPERL_MAGIC_isaPERL_MAGIC_isaelemPERL_MAGIC_lvrefPERL_MAGIC_nkeysPERL_MAGIC_nonelemPERL_MAGIC_overload_tablePERL_MAGIC_posPERL_MAGIC_qrPERL_MAGIC_regdataPERL_MAGIC_regdatumPERL_MAGIC_regex_globalPERL_MAGIC_rhashPERL_MAGIC_sharedPERL_MAGIC_shared_scalarPERL_MAGIC_sigPERL_MAGIC_sigelemPERL_MAGIC_substrPERL_MAGIC_svPERL_MAGIC_symtabPERL_MAGIC_taintPERL_MAGIC_tiedPERL_MAGIC_tiedelemPERL_MAGIC_tiedscalarPERL_MAGIC_utf8PERL_MAGIC_uvarPERL_MAGIC_uvar_elemPERL_MAGIC_vecPERL_MAGIC_vstringDescribed inperlguts.
SvTIED_objDescribed inperlinterp.
SvTIED_obj(SV *sv, MAGIC *mg)dump_mstatsWhen enabled by compiling with-DDEBUGGING_MSTATS, print out statistics about malloc as two lines of numbers, one showing the length of the free list for each size category, the second showing the number ofmallocs - frees for each size category.
s, if not NULL, is used as a phrase to include in the output, such as"after compilation".
void dump_mstats(const char *s)HASATTRIBUTE_MALLOCCan we handleGCC attribute for malloc-style functions.
HAS_MALLOC_GOOD_SIZEThis symbol, if defined, indicates that themalloc_good_size routine is available for use.
HAS_MALLOC_SIZEThis symbol, if defined, indicates that themalloc_size routine is available for use.
I_MALLOCMALLOCThis symbol, if defined, indicates to the C program that it should includemalloc/malloc.h.
#ifdef I_MALLOCMALLOC #include <mallocmalloc.h>#endifMYMALLOCThis symbol, if defined, indicates that we're using our own malloc.
NewxsafemallocThe XSUB-writer's interface to the Cmalloc function.
Memory obtained by this shouldONLY be freed with"Safefree".
In 5.9.3, Newx() and friends replace the older New() API, and drops the first parameter,x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG (see"PERL_MEM_LOG" in perlhacktips). The older API is still there for use in XS modules supporting older perls.
void Newx (void* ptr, int nitems, type)void* safemalloc(size_t size)NewxcThe XSUB-writer's interface to the Cmalloc function, with cast. See also"Newx".
Memory obtained by this shouldONLY be freed with"Safefree".
void Newxc(void* ptr, int nitems, type, cast)NewxzsafecallocThe XSUB-writer's interface to the Cmalloc function. The allocated memory is zeroed withmemzero. See also"Newx".
Memory obtained by this shouldONLY be freed with"Safefree".
void Newxz (void* ptr, int nitems, type)void* safecalloc(size_t nitems, size_t item_size)PERL_MALLOC_WRAPThis symbol, if defined, indicates that we'd like malloc wrap checks.
RenewsafereallocThe XSUB-writer's interface to the Crealloc function.
Memory obtained by this shouldONLY be freed with"Safefree".
void Renew (void* ptr, int nitems, type)void* saferealloc(void *ptr, size_t size)RenewcThe XSUB-writer's interface to the Crealloc function, with cast.
Memory obtained by this shouldONLY be freed with"Safefree".
void Renewc(void* ptr, int nitems, type, cast)SafefreeThe XSUB-writer's interface to the Cfree function.
This shouldONLY be used on memory obtained using"Newx" and friends.
void Safefree(void* ptr)safesyscallocSafe version of system's calloc()
Malloc_t safesyscalloc(MEM_SIZE elements, MEM_SIZE size)safesysfreeSafe version of system's free()
Free_t safesysfree(Malloc_t where)safesysmallocParanoid version of system's malloc()
Malloc_t safesysmalloc(MEM_SIZE nbytes)safesysreallocParanoid version of system's realloc()
Malloc_t safesysrealloc(Malloc_t where, MEM_SIZE nbytes)These functions are related to the method resolution order of perl classes Also seeperlmroapi.
HvMROMETADescribed inperlmroapi.
struct mro_meta * HvMROMETA(HV *hv)mro_get_from_nameReturns the previously registered mro with the givenname, or NULL if not registered. See"mro_register".
NOTE:mro_get_from_name must be explicitly called asPerl_mro_get_from_name with anaTHX_ parameter.
const struct mro_alg * Perl_mro_get_from_name(pTHX_ SV *name)mro_get_linear_isaReturns the mro linearisation for the given stash. By default, this will be whatevermro_get_linear_isa_dfs returns unless some other MRO is in effect for the stash. The return value is a read-only AV* whose values are string SVs giving class names.
You are responsible forSvREFCNT_inc() on the return value if you plan to store it anywhere semi-permanently (otherwise it might be deleted out from under you the next time the cache is invalidated).
AV * mro_get_linear_isa(HV *stash)MRO_GET_PRIVATE_DATADescribed inperlmroapi.
SV* MRO_GET_PRIVATE_DATA(struct mro_meta *const smeta, const struct mro_alg *const which)mro_method_changed_inInvalidates method caching on any child classes of the given stash, so that they might notice the changes in this one.
Ideally, all instances ofPL_sub_generation++ in perl source outside ofmro.c should be replaced by calls to this.
Perl automatically handles most of the common ways a method might be redefined. However, there are a few ways you could change a method in a stash without the cache code noticing, in which case you need to call this method afterwards:
1) Directly manipulating the stash HV entries from XS code.
2) Assigning a reference to a readonly scalar constant into a stash entry in order to create a constant subroutine (likeconstant.pm does).
This same method is available from pure perl via,mro::method_changed_in(classname).
void mro_method_changed_in(HV *stash)mro_registerRegisters a custom mro plugin. Seeperlmroapi for details on this and other mro functions.
NOTE:mro_register must be explicitly called asPerl_mro_register with anaTHX_ parameter.
void Perl_mro_register(pTHX_ const struct mro_alg *mro)mro_set_mroSetmeta to the value contained in the registered mro plugin whose name isname.
Croaks ifname hasn't been registered
NOTE:mro_set_mro must be explicitly called asPerl_mro_set_mro with anaTHX_ parameter.
void Perl_mro_set_mro(pTHX_ struct mro_meta * const meta, SV * const name)mro_set_private_dataDescribed inperlmroapi.
NOTE:mro_set_private_data must be explicitly called asPerl_mro_set_private_data with anaTHX_ parameter.
SV * Perl_mro_set_private_data(pTHX_ struct mro_meta * const smeta, const struct mro_alg * const which, SV * const data)dMULTICALLDeclare local variables for a multicall. See"LIGHTWEIGHT CALLBACKS" in perlcall.
dMULTICALL;MULTICALLMake a lightweight callback. See"LIGHTWEIGHT CALLBACKS" in perlcall.
MULTICALL;POP_MULTICALLClosing bracket for a lightweight callback. See"LIGHTWEIGHT CALLBACKS" in perlcall.
POP_MULTICALL;PUSH_MULTICALLOpening bracket for a lightweight callback. See"LIGHTWEIGHT CALLBACKS" in perlcall.
PUSH_MULTICALL(CV* the_cv);AtolDEPRECATED! It is planned to removeAtol from a future release of Perl. Do not use it for new code; remove it from existing code.
Described inperlhacktips.
Atol(const char * nptr)AtoulDEPRECATED! It is planned to removeAtoul from a future release of Perl. Do not use it for new code; remove it from existing code.
Described inperlhacktips.
Atoul(const char * nptr)Drand01This macro is to be used to generate uniformly distributed random numbers over the range [0., 1.[. You may have to supply an 'extern doubledrand48();' in your program since SunOS 4.1.3 doesn't provide you with anything relevant in its headers. See"HAS_DRAND48_PROTO".
double Drand01()GconvertThis preprocessor macro is defined to convert a floating point number to a string without a trailing decimal point. This emulates the behavior ofsprintf("%g"), but is sometimes much more efficient. Ifgconvert() is not available, butgcvt() drops the trailing decimal point, thengcvt() is used. If all else fails, a macro usingsprintf("%g") is used. Arguments for the Gconvert macro are: value, number of digits, whether trailing zeros should be retained, and the output buffer. The usual values are:
d_Gconvert='gconvert((x),(n),(t),(b))'d_Gconvert='gcvt((x),(n),(b))'d_Gconvert='sprintf((b),"%.*g",(n),(x))'The last two assume trailing zeros should not be kept.
char * Gconvert(double x, Size_t n, bool t, char * b)grok_atoUVparse a string, looking for a decimal unsigned integer.
On entry,pv points to the beginning of the string;valptr points to a UV that will receive the converted value, if found;endptr is either NULL or points to a variable that points to one byte beyond the point inpv that this routine should examine. Ifendptr is NULL,pv is assumed to be NUL-terminated.
Returns FALSE ifpv doesn't represent a valid unsigned integer value (with no leading zeros). Otherwise it returns TRUE, and sets*valptr to that value.
If you constrain the portion ofpv that is looked at by this function (by passing a non-NULLendptr), and if the initial bytes of that portion form a valid value, it will return TRUE, setting*endptr to the byte following the final digit of the value. But if there is no constraint at what's looked at, all ofpv must be valid in order for TRUE to be returned.*endptr is unchanged from its value on input if FALSE is returned;
The only characters this accepts are the decimal digits '0'..'9'.
As opposed toatoi(3) orstrtol(3),grok_atoUV does NOT allow optional leading whitespace, nor negative inputs. If such features are required, the calling code needs to explicitly implement those.
Note that this function returns FALSE for inputs that would overflow a UV, or have leading zeros. Thus a single0 is accepted, but not00 nor01,002,etc.
Background:atoi has severe problems with illegal inputs, it cannot be used for incremental parsing, and therefore should be avoidedatoi andstrtol are also affected by locale settings, which can also be seen as a bug (global state controlled by user environment).
bool grok_atoUV(const char *pv, UV *valptr, const char **endptr)grok_binconverts a string representing a binary number to numeric form.
On entrystart and*len_p give the string to scan,*flags gives conversion flags, andresult should beNULL or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT is set in*flags, encountering an invalid character (except NUL) will also trigger a warning. On return*len_p is set to the length of the scanned string, and*flags gives output flags.
If the value is <=UV_MAX it is returned as a UV, the output flags are clear, and nothing is written to*result. If the value is >UV_MAX,grok_bin returnsUV_MAX, setsPERL_SCAN_GREATER_THAN_UV_MAX in the output flags, and writes an approximation of the correct value into*result (which is an NV; or the approximation is discarded ifresult is NULL).
The binary number may optionally be prefixed with"0b" or"b" unlessPERL_SCAN_DISALLOW_PREFIX is set in*flags on entry.
IfPERL_SCAN_ALLOW_UNDERSCORES is set in*flags then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
UV grok_bin(const char *start, STRLEN *len_p, I32 *flags, NV *result)grok_hexconverts a string representing a hex number to numeric form.
On entrystart and*len_p give the string to scan,*flags gives conversion flags, andresult should beNULL or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT is set in*flags, encountering an invalid character (except NUL) will also trigger a warning. On return*len_p is set to the length of the scanned string, and*flags gives output flags.
If the value is <=UV_MAX it is returned as a UV, the output flags are clear, and nothing is written to*result. If the value is >UV_MAX,grok_hex returnsUV_MAX, setsPERL_SCAN_GREATER_THAN_UV_MAX in the output flags, and writes an approximation of the correct value into*result (which is an NV; or the approximation is discarded ifresult is NULL).
The hex number may optionally be prefixed with"0x" or"x" unlessPERL_SCAN_DISALLOW_PREFIX is set in*flags on entry.
IfPERL_SCAN_ALLOW_UNDERSCORES is set in*flags then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
UV grok_hex(const char *start, STRLEN *len_p, I32 *flags, NV *result)grok_infnanHelper forgrok_number(), accepts various ways of spelling "infinity" or "not a number", and returns one of the following flag combinations:
IS_NUMBER_INFINITYIS_NUMBER_NANIS_NUMBER_INFINITY | IS_NUMBER_NEGIS_NUMBER_NAN | IS_NUMBER_NEG0possibly |-ed withIS_NUMBER_TRAILING.
If an infinity or a not-a-number is recognized,*sp will point to one byte past the end of the recognized string. If the recognition fails, zero is returned, and*sp will not move.
int grok_infnan(const char **sp, const char *send)grok_numberIdentical togrok_number_flags() withflags set to zero.
int grok_number(const char *pv, STRLEN len, UV *valuep)grok_number_flagsRecognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise it is a bit-ORed combination ofIS_NUMBER_IN_UV,IS_NUMBER_GREATER_THAN_UV_MAX,IS_NUMBER_NOT_INT,IS_NUMBER_NEG,IS_NUMBER_INFINITY,IS_NUMBER_NAN (defined in perl.h).
If the value of the number can fit in a UV, it is returned in*valuep.IS_NUMBER_IN_UV will be set to indicate that*valuep is valid,IS_NUMBER_IN_UV will never be set unless*valuep is valid, but*valuep may have been assigned to during processing even thoughIS_NUMBER_IN_UV is not set on return. Ifvaluep isNULL,IS_NUMBER_IN_UV will be set for the same cases as whenvaluep is non-NULL, but no actual assignment (or SEGV) will occur.
IS_NUMBER_NOT_INT will be set withIS_NUMBER_IN_UV if trailing decimals were seen (in which case*valuep gives the true value truncated to an integer), andIS_NUMBER_NEG if the number is negative (in which case*valuep holds the absolute value).IS_NUMBER_IN_UV is not set ife notation was used or the number is larger than a UV.
flags allows onlyPERL_SCAN_TRAILING, which allows for trailing non-numeric text on an otherwise successfulgrok, settingIS_NUMBER_TRAILING on the result.
int grok_number_flags(const char *pv, STRLEN len, UV *valuep, U32 flags)GROK_NUMERIC_RADIXA synonym for"grok_numeric_radix"
bool GROK_NUMERIC_RADIX(NN const char **sp, NN const char *send)grok_numeric_radixScan and skip for a numeric decimal separator (radix).
bool grok_numeric_radix(const char **sp, const char *send)grok_octconverts a string representing an octal number to numeric form.
On entrystart and*len_p give the string to scan,*flags gives conversion flags, andresult should beNULL or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT is set in*flags, encountering an invalid character (except NUL) will also trigger a warning. On return*len_p is set to the length of the scanned string, and*flags gives output flags.
If the value is <=UV_MAX it is returned as a UV, the output flags are clear, and nothing is written to*result. If the value is >UV_MAX,grok_oct returnsUV_MAX, setsPERL_SCAN_GREATER_THAN_UV_MAX in the output flags, and writes an approximation of the correct value into*result (which is an NV; or the approximation is discarded ifresult is NULL).
IfPERL_SCAN_ALLOW_UNDERSCORES is set in*flags then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
ThePERL_SCAN_DISALLOW_PREFIX flag is always treated as being set for this function.
UV grok_oct(const char *start, STRLEN *len_p, I32 *flags, NV *result)isinfnanPerl_isinfnan() is a utility function that returns true if the NV argument is either an infinity or aNaN, false otherwise. To test in more detail, usePerl_isinf() andPerl_isnan().
This is also the logical inverse of Perl_isfinite().
bool isinfnan(NV nv)my_atofatof(3), but properly works with Perl locale handling, accepting a dot radix character always, but also the current locale's radix character if and only if called from within the lexical scope of a Perluse locale statement.
N.B.s must be NUL terminated.
NV my_atof(const char *s)my_strtodThis function is equivalent to the libc strtod() function, and is available even on platforms that lack plain strtod(). Its return value is the best available precision depending on platform capabilities andConfigure options.
It properly handles the locale radix character, meaning it expects a dot except when called from within the scope ofuse locale, in which case the radix character should be that specified by the current locale.
The synonym Strtod() may be used instead.
NV my_strtod(const char * const s, char **e)PERL_ABSTypelessabs orfabs,etc. (The usage below indicates it is for integers, but it works for any type.) Use instead of these, since the C library ones force their argument to be what it is expecting, potentially leading to disaster. But also beware that this evaluates its argument twice, so nox++.
int PERL_ABS(int x)Perl_acosPerl_asinPerl_atanPerl_atan2Perl_ceilPerl_cosPerl_coshPerl_expPerl_floorPerl_fmodPerl_frexpPerl_isfinitePerl_isinfPerl_isnanPerl_ldexpPerl_logPerl_log10Perl_modfPerl_powPerl_sinPerl_sinhPerl_sqrtPerl_tanPerl_tanhThese perform the corresponding mathematical operation on the operand(s), using the libc function designed for the task that has just enough precision for an NV on this platform. If no such function with sufficient precision exists, the highest precision one available is used.
NV Perl_acos (NV x)NV Perl_asin (NV x)NV Perl_atan (NV x)NV Perl_atan2 (NV x, NV y)NV Perl_ceil (NV x)NV Perl_cos (NV x)NV Perl_cosh (NV x)NV Perl_exp (NV x)NV Perl_floor (NV x)NV Perl_fmod (NV x, NV y)NV Perl_frexp (NV x, int *exp)IV Perl_isfinite(NV x)IV Perl_isinf (NV x)IV Perl_isnan (NV x)NV Perl_ldexp (NV x, int exp)NV Perl_log (NV x)NV Perl_log10 (NV x)NV Perl_modf (NV x, NV *iptr)NV Perl_pow (NV x, NV y)NV Perl_sin (NV x)NV Perl_sinh (NV x)NV Perl_sqrt (NV x)NV Perl_tan (NV x)NV Perl_tanh (NV x)Perl_signbitNOTE:Perl_signbit isexperimental and may change or be removed without notice.
Return a non-zero integer if the sign bit on an NV is set, and 0 if it is not.
IfConfigure detects this system has asignbit() that will work with our NVs, then we just use it via the#define inperl.h. Otherwise, fall back on this implementation. The main use of this function is catching-0.0.
Configure notes: This function is called'Perl_signbit' instead of a plain'signbit' because it is easy to imagine a system having asignbit() function or macro that doesn't happen to work with our particular choice of NVs. We shouldn't just re-#definesignbit asPerl_signbit and expect the standard system headers to be happy. Also, this is a no-context function (nopTHX_) becausePerl_signbit() is usually re-#defined inperl.h as a simple macro call to the system'ssignbit(). Users should just always callPerl_signbit().
int Perl_signbit(NV f)PL_hexdigitThis array, indexed by an integer, converts that value into the character that represents it. For example, if the input is 8, the return will be a string whose first character is '8'. What is actually returned is a pointer into a string. All you are interested in is the first character of that string. To get uppercase letters (for the values 10..15), add 16 to the index. Hence,PL_hexdigit[11] is'b', andPL_hexdigit[11+16] is'B'. Adding 16 to an index whose representation is '0'..'9' yields the same as not adding 16. Indices outside the range 0..31 result in (bad) undedefined behavior.
READ_XDIGITReturns the value of an ASCII-range hex digit and advances the string pointer. Behaviour is only well defined when isXDIGIT(*str) is true.
U8 READ_XDIGIT(char str*)scan_binFor backwards compatibility. Usegrok_bin instead.
NV scan_bin(const char *start, STRLEN len, STRLEN *retlen)scan_hexFor backwards compatibility. Usegrok_hex instead.
NV scan_hex(const char *start, STRLEN len, STRLEN *retlen)scan_octFor backwards compatibility. Usegrok_oct instead.
NV scan_oct(const char *start, STRLEN len, STRLEN *retlen)seedDrand01This symbol defines the macro to be used in seeding the random number generator (see"Drand01").
void seedDrand01(Rand_seed_t x)StrtodThis is a synonym for"my_strtod".
NV Strtod(NN const char * const s, NULLOK char ** e)StrtolPlatform and configuration independentstrtol. This expands to the appropriatestrotol-like function based on the platform andConfigure options>. For example it could expand tostrtoll orstrtoq instead ofstrtol.
NV Strtol(NN const char * const s, NULLOK char ** e, int base)StrtoulPlatform and configuration independentstrtoul. This expands to the appropriatestrotoul-like function based on the platform andConfigure options>. For example it could expand tostrtoull orstrtouq instead ofstrtoul.
NV Strtoul(NN const char * const s, NULLOK char ** e, int base)alloccopstashNOTE:alloccopstash isexperimental and may change or be removed without notice.
Available only under threaded builds, this function allocates an entry inPL_stashpad for the stash passed to it.
PADOFFSET alloccopstash(HV *hv)block_endHandles compile-time scope exit.floor is the savestack index returned byblock_start, andseq is the body of the block. Returns the block, possibly modified.
OP * block_end(I32 floor, OP *seq)block_startHandles compile-time scope entry. Arranges for hints to be restored on block exit and also handles pad sequence numbers to make lexical variables scope right. Returns a savestack index for use withblock_end.
int block_start(int full)ck_entersub_args_listPerforms the default fixup of the arguments part of anentersub op tree. This consists of applying list context to each of the argument ops. This is the standard treatment used on a call marked with&, or a method call, or a call through a subroutine reference, or any other call where the callee can't be identified at compile time, or a call where the callee has no prototype.
OP * ck_entersub_args_list(OP *entersubop)ck_entersub_args_protoPerforms the fixup of the arguments part of anentersub op tree based on a subroutine prototype. This makes various modifications to the argument ops, from applying context up to insertingrefgen ops, and checking the number and syntactic types of arguments, as directed by the prototype. This is the standard treatment used on a subroutine call, not marked with&, where the callee can be identified at compile time and has a prototype.
protosv supplies the subroutine prototype to be applied to the call. It may be a normal defined scalar, of which the string value will be used. Alternatively, for convenience, it may be a subroutine object (aCV* that has been cast toSV*) which has a prototype. The prototype supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of arguments, a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. In the error message, the callee is referred to by the name defined by thenamegv parameter.
OP * ck_entersub_args_proto(OP *entersubop, GV *namegv, SV *protosv)ck_entersub_args_proto_or_listPerforms the fixup of the arguments part of anentersub op tree either based on a subroutine prototype or using default list-context processing. This is the standard treatment used on a subroutine call, not marked with&, where the callee can be identified at compile time.
protosv supplies the subroutine prototype to be applied to the call, or indicates that there is no prototype. It may be a normal scalar, in which case if it is defined then the string value will be used as a prototype, and if it is undefined then there is no prototype. Alternatively, for convenience, it may be a subroutine object (aCV* that has been cast toSV*), of which the prototype will be used if it has one. The prototype (or lack thereof) supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of arguments, a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. In the error message, the callee is referred to by the name defined by thenamegv parameter.
OP * ck_entersub_args_proto_or_list(OP *entersubop, GV *namegv, SV *protosv)cv_const_svIfcv is a constant sub eligible for inlining, returns the constant value returned by the sub. Otherwise, returnsNULL.
Constant subs can be created withnewCONSTSUB or as described in"Constant Functions" in perlsub.
SV * cv_const_sv(const CV * const cv)cv_get_call_checkerThe original form of"cv_get_call_checker_flags", which does not return checker flags. When using a checker function returned by this function, it is only safe to call it with a genuine GV as itsnamegv argument.
void cv_get_call_checker(CV *cv, Perl_call_checker *ckfun_p, SV **ckobj_p)cv_get_call_checker_flagsRetrieves the function that will be used to fix up a call tocv. Specifically, the function is applied to anentersub op tree for a subroutine call, not marked with&, where the callee can be identified at compile time ascv.
The C-level function pointer is returned in*ckfun_p, an SV argument for it is returned in*ckobj_p, and control flags are returned in*ckflags_p. The function is intended to be called in this manner:
entersubop = (*ckfun_p)(aTHX_ entersubop, namegv, (*ckobj_p));In this call,entersubop is a pointer to theentersub op, which may be replaced by the check function, andnamegv supplies the name that should be used by the check function to refer to the callee of theentersub op if it needs to emit any diagnostics. It is permitted to apply the check function in non-standard situations, such as to a call to a different subroutine or to a method call.
namegv may not actually be a GV. If theCALL_CHECKER_REQUIRE_GV bit is clear in*ckflags_p, it is permitted to pass a CV or other SV instead, anything that can be used as the first argument to"cv_name". If theCALL_CHECKER_REQUIRE_GV bit is set in*ckflags_p then the check function requiresnamegv to be a genuine GV.
By default, the check function isPerl_ck_entersub_args_proto_or_list, the SV parameter iscv itself, and theCALL_CHECKER_REQUIRE_GV flag is clear. This implements standard prototype processing. It can be changed, for a particular subroutine, by"cv_set_call_checker_flags".
If theCALL_CHECKER_REQUIRE_GV bit is set ingflags then it indicates that the caller only knows about the genuine GV version ofnamegv, and accordingly the corresponding bit will always be set in*ckflags_p, regardless of the check function's recorded requirements. If theCALL_CHECKER_REQUIRE_GV bit is clear ingflags then it indicates the caller knows about the possibility of passing something other than a GV asnamegv, and accordingly the corresponding bit may be either set or clear in*ckflags_p, indicating the check function's recorded requirements.
gflags is a bitset passed intocv_get_call_checker_flags, in which only theCALL_CHECKER_REQUIRE_GV bit currently has a defined meaning (for which see above). All other bits should be clear.
void cv_get_call_checker_flags(CV *cv, U32 gflags, Perl_call_checker *ckfun_p, SV **ckobj_p, U32 *ckflags_p)cv_set_call_checkerThe original form of"cv_set_call_checker_flags", which passes it theCALL_CHECKER_REQUIRE_GV flag for backward-compatibility. The effect of that flag setting is that the check function is guaranteed to get a genuine GV as itsnamegv argument.
void cv_set_call_checker(CV *cv, Perl_call_checker ckfun, SV *ckobj)cv_set_call_checker_flagsSets the function that will be used to fix up a call tocv. Specifically, the function is applied to anentersub op tree for a subroutine call, not marked with&, where the callee can be identified at compile time ascv.
The C-level function pointer is supplied inckfun, an SV argument for it is supplied inckobj, and control flags are supplied inckflags. The function should be defined like this:
STATIC OP * ckfun(pTHX_ OP *op, GV *namegv, SV *ckobj)It is intended to be called in this manner:
entersubop = ckfun(aTHX_ entersubop, namegv, ckobj);In this call,entersubop is a pointer to theentersub op, which may be replaced by the check function, andnamegv supplies the name that should be used by the check function to refer to the callee of theentersub op if it needs to emit any diagnostics. It is permitted to apply the check function in non-standard situations, such as to a call to a different subroutine or to a method call.
namegv may not actually be a GV. For efficiency, perl may pass a CV or other SV instead. Whatever is passed can be used as the first argument to"cv_name". You can force perl to pass a GV by includingCALL_CHECKER_REQUIRE_GV in theckflags.
ckflags is a bitset, in which only theCALL_CHECKER_REQUIRE_GV bit currently has a defined meaning (for which see above). All other bits should be clear.
The current setting for a particular CV can be retrieved by"cv_get_call_checker_flags".
void cv_set_call_checker_flags(CV *cv, Perl_call_checker ckfun, SV *ckobj, U32 ckflags)finalize_optreeThis function finalizes the optree. Should be called directly after the complete optree is built. It does some additional checking which can't be done in the normalck_xxx functions and makes the tree thread-safe.
void finalize_optree(OP *o)forbid_outofblock_opsNOTE:forbid_outofblock_ops isexperimental and may change or be removed without notice.
Checks an optree that implements a block, to ensure there are no control-flow ops that attempt to leave the block. AnyOP_RETURN is forbidden, as is anyOP_GOTO. Loops are analysed, so any LOOPEX op (OP_NEXT,OP_LAST orOP_REDO) that affects a loop that contains it within the block are permitted, but those that do not are forbidden.
If any of these forbidden constructions are detected, an exception is thrown by using the op name and the blockname argument to construct a suitable message.
This function alone is not sufficient to ensure the optree does not perform any of these forbidden activities during runtime, as it might call a different function that performs a non-local LOOPEX, or a string-eval() that performs agoto, or various other things. It is intended purely as a compile-time check for those that could be detected statically. Additional runtime checks may be required depending on the circumstance it is used for.
Note currently thatallOP_GOTO ops are forbidden, even in cases where they might otherwise be safe to execute. This may be permitted in a later version.
void forbid_outofblock_ops(OP *o, const char *blockname)LINKLISTGiven the root of an optree, link the tree in execution order using theop_next pointers and return the first op executed. If this has already been done, it will not be redone, ando->op_next will be returned. Ifo->op_next is not already set,o should be at least anUNOP.
OP* LINKLIST(OP *o)newANONATTRSUBConstruct a nameless (anonymous) Perl subroutine, also performing some surrounding jobs.
This is the same as"newATTRSUB_x" in perlintern with itso_is_gv parameter set to FALSE, and itso parameter to NULL. For more details, see"newATTRSUB_x" in perlintern.
OP * newANONATTRSUB(I32 floor, OP *proto, OP *attrs, OP *block)newANONHASHConstructs, checks, and returns an anonymous hash op.
OP * newANONHASH(OP *o)newANONLISTConstructs, checks, and returns an anonymous list op.
OP * newANONLIST(OP *o)newANONSUBConstruct a nameless (anonymous) Perl subroutine without attributes, also performing some surrounding jobs.
This is the same as"newATTRSUB_x" in perlintern with itso_is_gv parameter set to FALSE, and itso andattrs parameters to NULL. For more details, see"newATTRSUB_x" in perlintern.
OP * newANONSUB(I32 floor, OP *proto, OP *block)newARGDEFELEMOPConstructs and returns a newOP_ARGDEFELEM op which provides a defaulting expression given byexpr for the signature parameter at the index given byargindex. The expression optree is consumed by this function and becomes part of the returned optree.
OP * newARGDEFELEMOP(I32 flags, OP *expr, I32 argindex)newASSIGNOPConstructs, checks, and returns an assignment op.left andright supply the parameters of the assignment; they are consumed by this function and become part of the constructed op tree.
Ifoptype isOP_ANDASSIGN,OP_ORASSIGN, orOP_DORASSIGN, then a suitable conditional optree is constructed. Ifoptype is the opcode of a binary operator, such asOP_BIT_OR, then an op is constructed that performs the binary operation and assigns the result to the left argument. Either way, ifoptype is non-zero thenflags has no effect.
Ifoptype is zero, then a plain scalar or list assignment is constructed. Which type of assignment it is is automatically determined.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 or 2 is automatically set as required.
OP * newASSIGNOP(I32 flags, OP *left, I32 optype, OP *right)newATTRSUBConstruct a Perl subroutine, also performing some surrounding jobs, returning a pointer to the constructed subroutine.
This is the same as"newATTRSUB_x" in perlintern with itso_is_gv parameter set to FALSE. This means that ifo is null, the new sub will be anonymous; otherwise the name will be derived fromo in the way described (as with all other details) in"newATTRSUB_x" in perlintern.
CV * newATTRSUB(I32 floor, OP *o, OP *proto, OP *attrs, OP *block)newAVREFConstructs, checks, and returns an arrary reference op.
OP * newAVREF(OP *o)newBINOPConstructs, checks, and returns an op of any binary type.type is the opcode.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 or 2 is automatically set as required.first andlast supply up to two ops to be the direct children of the binary op; they are consumed by this function and become part of the constructed op tree.
OP * newBINOP(I32 type, I32 flags, OP *first, OP *last)newCONDOPConstructs, checks, and returns a conditional-expression (cond_expr) op.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 is automatically set.first supplies the expression selecting between the two branches, andtrueop andfalseop supply the branches; they are consumed by this function and become part of the constructed op tree.
OP * newCONDOP(I32 flags, OP *first, OP *trueop, OP *falseop)newCONSTSUBnewCONSTSUB_flagsConstruct a constant subroutine, also performing some surrounding jobs. A scalar constant-valued subroutine is eligible for inlining at compile-time, and in Perl code can be created bysub FOO () { 123 }. Other kinds of constant subroutine have other treatment.
The subroutine will have an empty prototype and will ignore any arguments when called. Its constant behaviour is determined bysv. Ifsv is null, the subroutine will yield an empty list. Ifsv points to a scalar, the subroutine will always yield that scalar. Ifsv points to an array, the subroutine will always yield a list of the elements of that array in list context, or the number of elements in the array in scalar context. This function takes ownership of one counted reference to the scalar or array, and will arrange for the object to live as long as the subroutine does. Ifsv points to a scalar then the inlining assumes that the value of the scalar will never change, so the caller must ensure that the scalar is not subsequently written to. Ifsv points to an array then no such assumption is made, so it is ostensibly safe to mutate the array or its elements, but whether this is really supported has not been determined.
The subroutine will haveCvFILE set according toPL_curcop. Other aspects of the subroutine will be left in their default state. The caller is free to mutate the subroutine beyond its initial state after this function has returned.
Ifname is null then the subroutine will be anonymous, with itsCvGV referring to an__ANON__ glob. Ifname is non-null then the subroutine will be named accordingly, referenced by the appropriate glob.
name is a string, giving a sigilless symbol name. For/newCONSTSUB,name is NUL-terminated, interpreted as Latin-1.
For/newCONSTSUB_flags,name has lengthlen bytes, hence may contain embedded NULs. It is interpreted as UTF-8 ifflags has theSVf_UTF8 bit set, and Latin-1 otherwise.flags should not have bits set other thanSVf_UTF8.
The name may be either qualified or unqualified. If the name is unqualified then it defaults to being in the stash specified bystash if that is non-null, or toPL_curstash ifstash is null. The symbol is always added to the stash if necessary, withGV_ADDMULTI semantics.
If there is already a subroutine of the specified name, then the new sub will replace the existing one in the glob. A warning may be generated about the redefinition.
If the subroutine has one of a few special names, such asBEGIN orEND, then it will be claimed by the appropriate queue for automatic running of phase-related subroutines. In this case the relevant glob will be left not containing any subroutine, even if it did contain one before. Execution of the subroutine will likely be a no-op, unlesssv was a tied array or the caller modified the subroutine in some interesting way before it was executed. In the case ofBEGIN, the treatment is buggy: the sub will be executed when only half built, and may be deleted prematurely, possibly causing a crash.
The function returns a pointer to the constructed subroutine. If the sub is anonymous then ownership of one counted reference to the subroutine is transferred to the caller. If the sub is named then the caller does not get ownership of a reference. In most such cases, where the sub has a non-phase name, the sub will be alive at the point it is returned by virtue of being contained in the glob that names it. A phase-named subroutine will usually be alive by virtue of the reference owned by the phase's automatic run queue. ABEGIN subroutine may have been destroyed already by the time this function returns, but currently bugs occur in that case before the caller gets control. It is the caller's responsibility to ensure that it knows which of these situations applies.
CV * newCONSTSUB (HV *stash, const char *name, SV *sv)CV * newCONSTSUB_flags(HV *stash, const char *name, STRLEN len, U32 flags, SV *sv)newCVREFConstructs, checks, and returns a code reference op.
OP * newCVREF(I32 flags, OP *o)newDEFEROPNOTE:newDEFEROP isexperimental and may change or be removed without notice.
Constructs and returns a deferred-block statement that implements thedefer semantics. Theblock optree is consumed by this function and becomes part of the returned optree.
Theflags argument carries additional flags to set on the returned op, including theop_private field.
OP * newDEFEROP(I32 flags, OP *block)newDEFSVOPConstructs and returns an op to access$_.
OP * newDEFSVOP()newFOROPConstructs, checks, and returns an op tree expressing aforeach loop (iteration through a list of values). This is a heavyweight loop, with structure that allows exiting the loop bylast and suchlike.
sv optionally supplies the variable(s) that will be aliased to each item in turn; if null, it defaults to$_.expr supplies the list of values to iterate over.block supplies the main body of the loop, andcont optionally supplies acontinue block that operates as a second half of the body. All of these optree inputs are consumed by this function and become part of the constructed op tree.
flags gives the eight bits ofop_flags for theleaveloop op and, shifted up eight bits, the eight bits ofop_private for theleaveloop op, except that (in both cases) some bits will be set automatically.
OP * newFOROP(I32 flags, OP *sv, OP *expr, OP *block, OP *cont)newGIVENOPConstructs, checks, and returns an op tree expressing agiven block.cond supplies the expression to whose value$_ will be locally aliased, andblock supplies the body of thegiven construct; they are consumed by this function and become part of the constructed op tree.defsv_off must be zero (it used to identity the pad slot of lexical $_).
OP * newGIVENOP(OP *cond, OP *block, PADOFFSET defsv_off)newGVOPConstructs, checks, and returns an op of any type that involves an embedded reference to a GV.type is the opcode.flags gives the eight bits ofop_flags.gv identifies the GV that the op should reference; calling this function does not transfer ownership of any reference to it.
OP * newGVOP(I32 type, I32 flags, GV *gv)newGVREFConstructs, checks, and returns a glob reference op.
OP * newGVREF(I32 type, OP *o)newHVREFConstructs, checks, and returns a hash reference op.
OP * newHVREF(OP *o)newLISTOPConstructs, checks, and returns an op of any list type.type is the opcode.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically if required.first andlast supply up to two ops to be direct children of the list op; they are consumed by this function and become part of the constructed op tree.
For most list operators, the check function expects all the kid ops to be present already, so callingnewLISTOP(OP_JOIN, ...) (e.g.) is not appropriate. What you want to do in that case is create an op of typeOP_LIST, append more children to it, and then call"op_convert_list". See"op_convert_list" for more information.
If a compiletime-known fixed list of child ops is required, the"newLISTOPn" function can be used as a convenient shortcut, avoiding the need to create a temporary plainOP_LIST in a new variable.
OP * newLISTOP(I32 type, I32 flags, OP *first, OP *last)newLISTOPnConstructs, checks, and returns an op of any list type.type is the opcode.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically if required. The variable number of arguments afterflags must all be OP pointers, terminated by a finalNULL pointer. These will all be consumed as direct children of the list op and become part of the constructed op tree.
Do not forget to end the arguments list with aNULL pointer.
This function is useful as a shortcut to performing the sequence ofnewLISTOP(),op_append_elem() on each element and finalop_convert_list() in the case where a compiletime-known fixed sequence of child ops is required. If a variable number of elements are required, or for splicing in an entire sub-list of child ops, see instead"newLISTOP" and"op_convert_list".
OP * newLISTOPn(I32 type, I32 flags, ...)newLOGOPConstructs, checks, and returns a logical (flow control) op.type is the opcode.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 is automatically set.first supplies the expression controlling the flow, andother supplies the side (alternate) chain of ops; they are consumed by this function and become part of the constructed op tree.
OP * newLOGOP(I32 optype, I32 flags, OP *first, OP *other)newLOOPEXConstructs, checks, and returns a loop-exiting op (such asgoto orlast).type is the opcode.label supplies the parameter determining the target of the op; it is consumed by this function and becomes part of the constructed op tree.
OP * newLOOPEX(I32 type, OP *label)newLOOPOPConstructs, checks, and returns an op tree expressing a loop. This is only a loop in the control flow through the op tree; it does not have the heavyweight loop structure that allows exiting the loop bylast and suchlike.flags gives the eight bits ofop_flags for the top-level op, except that some bits will be set automatically as required.expr supplies the expression controlling loop iteration, andblock supplies the body of the loop; they are consumed by this function and become part of the constructed op tree.debuggable is currently unused and should always be 1.
OP * newLOOPOP(I32 flags, I32 debuggable, OP *expr, OP *block)newMETHOPConstructs, checks, and returns an op of method type with a method name evaluated at runtime.type is the opcode.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 is automatically set.dynamic_meth supplies an op which evaluates method name; it is consumed by this function and become part of the constructed op tree. Supported optypes:OP_METHOD.
OP * newMETHOP(I32 type, I32 flags, OP *dynamic_meth)newMETHOP_namedConstructs, checks, and returns an op of method type with a constant method name.type is the opcode.flags gives the eight bits ofop_flags, and, shifted up eight bits, the eight bits ofop_private.const_meth supplies a constant method name; it must be a shared COW string. Supported optypes:OP_METHOD_NAMED.
OP * newMETHOP_named(I32 type, I32 flags, SV * const_meth)newNULLLISTConstructs, checks, and returns a newstub op, which represents an empty list expression.
OP * newNULLLIST()newOPConstructs, checks, and returns an op of any base type (any type that has no extra fields).type is the opcode.flags gives the eight bits ofop_flags, and, shifted up eight bits, the eight bits ofop_private.
OP * newOP(I32 optype, I32 flags)newPADOPConstructs, checks, and returns an op of any type that involves a reference to a pad element.type is the opcode.flags gives the eight bits ofop_flags. A pad slot is automatically allocated, and is populated withsv; this function takes ownership of one reference to it.
This function only exists if Perl has been compiled to use ithreads.
OP * newPADOP(I32 type, I32 flags, SV *sv)newPMOPConstructs, checks, and returns an op of any pattern matching type.type is the opcode.flags gives the eight bits ofop_flags and, shifted up eight bits, the eight bits ofop_private.
OP * newPMOP(I32 type, I32 flags)newPVOPConstructs, checks, and returns an op of any type that involves an embedded C-level pointer (PV).type is the opcode.flags gives the eight bits ofop_flags.pv supplies the C-level pointer. Depending on the op type, the memory referenced bypv may be freed when the op is destroyed. If the op is of a freeing type,pv must have been allocated usingPerlMemShared_malloc.
OP * newPVOP(I32 type, I32 flags, char *pv)newRANGEConstructs and returns arange op, with subordinateflip andflop ops.flags gives the eight bits ofop_flags for theflip op and, shifted up eight bits, the eight bits ofop_private for both theflip andrange ops, except that the bit with value 1 is automatically set.left andright supply the expressions controlling the endpoints of the range; they are consumed by this function and become part of the constructed op tree.
OP * newRANGE(I32 flags, OP *left, OP *right)newSLICEOPConstructs, checks, and returns anlslice (list slice) op.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 or 2 is automatically set as required.listval andsubscript supply the parameters of the slice; they are consumed by this function and become part of the constructed op tree.
OP * newSLICEOP(I32 flags, OP *subscript, OP *listop)newSTATEOPConstructs a state op (COP). The state op is normally anextstate op, but will be adbstate op if debugging is enabled for currently-compiled code. The state op is populated fromPL_curcop (orPL_compiling). Iflabel is non-null, it supplies the name of a label to attach to the state op; this function takes ownership of the memory pointed at bylabel, and will free it.flags gives the eight bits ofop_flags for the state op.
Ifo is null, the state op is returned. Otherwise the state op is combined witho into alineseq list op, which is returned.o is consumed by this function and becomes part of the returned op tree.
OP * newSTATEOP(I32 flags, char *label, OP *o)newSUBConstruct a Perl subroutine without attributes, and also performing some surrounding jobs, returning a pointer to the constructed subroutine.
This is the same as"newATTRSUB_x" in perlintern with itso_is_gv parameter set to FALSE, and itsattrs parameter to NULL. This means that ifo is null, the new sub will be anonymous; otherwise the name will be derived fromo in the way described (as with all other details) in"newATTRSUB_x" in perlintern.
CV * newSUB(I32 floor, OP *o, OP *proto, OP *block)newSVOPConstructs, checks, and returns an op of any type that involves an embedded SV.type is the opcode.flags gives the eight bits ofop_flags.sv gives the SV to embed in the op; this function takes ownership of one reference to it.
OP * newSVOP(I32 type, I32 flags, SV *sv)newSVREFConstructs, checks, and returns a scalar reference op.
OP * newSVREF(OP *o)newTRYCATCHOPNOTE:newTRYCATCHOP isexperimental and may change or be removed without notice.
Constructs and returns a conditional execution statement that implements thetry/catch semantics. First the op tree intryblock is executed, inside a context that traps exceptions. If an exception occurs then the optree incatchblock is executed, with the trapped exception set into the lexical variable given bycatchvar (which must be an op of typeOP_PADSV). All the optrees are consumed by this function and become part of the returned op tree.
Theflags argument is currently ignored.
OP * newTRYCATCHOP(I32 flags, OP *tryblock, OP *catchvar, OP *catchblock)newUNOPConstructs, checks, and returns an op of any unary type.type is the opcode.flags gives the eight bits ofop_flags, except thatOPf_KIDS will be set automatically if required, and, shifted up eight bits, the eight bits ofop_private, except that the bit with value 1 is automatically set.first supplies an optional op to be the direct child of the unary op; it is consumed by this function and become part of the constructed op tree.
OP * newUNOP(I32 type, I32 flags, OP *first)newUNOP_AUXSimilar tonewUNOP, but creates anUNOP_AUX struct instead, withop_aux initialised toaux
OP * newUNOP_AUX(I32 type, I32 flags, OP *first, UNOP_AUX_item *aux)newWHENOPConstructs, checks, and returns an op tree expressing awhen block.cond supplies the test expression, andblock supplies the block that will be executed if the test evaluates to true; they are consumed by this function and become part of the constructed op tree.cond will be interpreted DWIMically, often as a comparison against$_, and may be null to generate adefault block.
OP * newWHENOP(OP *cond, OP *block)newWHILEOPConstructs, checks, and returns an op tree expressing awhile loop. This is a heavyweight loop, with structure that allows exiting the loop bylast and suchlike.
loop is an optional preconstructedenterloop op to use in the loop; if it is null then a suitable op will be constructed automatically.expr supplies the loop's controlling expression.block supplies the main body of the loop, andcont optionally supplies acontinue block that operates as a second half of the body. All of these optree inputs are consumed by this function and become part of the constructed op tree.
flags gives the eight bits ofop_flags for theleaveloop op and, shifted up eight bits, the eight bits ofop_private for theleaveloop op, except that (in both cases) some bits will be set automatically.debuggable is currently unused and should always be 1.has_my can be supplied as true to force the loop body to be enclosed in its own scope.
OP * newWHILEOP(I32 flags, I32 debuggable, LOOP *loop, OP *expr, OP *block, OP *cont, I32 has_my)newXSUsed byxsubpp to hook up XSUBs as Perl subs.filename needs to be static storage, as it is used directly as CvFILE(), without a copy being made.
OA_BASEOPOA_BINOPOA_COPOA_LISTOPOA_LOGOPOA_LOOPOA_PADOPOA_PMOPOA_PVOP_OR_SVOPOA_SVOPOA_UNOPDescribed inperlguts.
op_append_elemAppend an item to the list of ops contained directly within a list-type op, returning the lengthened list.first is the list-type op, andlast is the op to append to the list.optype specifies the intended opcode for the list. Iffirst is not already a list of the right type, it will be upgraded into one. If eitherfirst orlast is null, the other is returned unchanged.
OP * op_append_elem(I32 optype, OP *first, OP *last)op_append_listConcatenate the lists of ops contained directly within two list-type ops, returning the combined list.first andlast are the list-type ops to concatenate.optype specifies the intended opcode for the list. If eitherfirst orlast is not already a list of the right type, it will be upgraded into one. If eitherfirst orlast is null, the other is returned unchanged.
OP * op_append_list(I32 optype, OP *first, OP *last)OP_CLASSReturn the class of the provided OP: that is, which of the *OP structures it uses. For core ops this currently gets the information out ofPL_opargs, which does not always accurately reflect the type used; in v5.26 onwards, see also the function"op_class" which can do a better job of determining the used type.
For custom ops the type is returned from the registration, and it is up to the registree to ensure it is accurate. The value returned will be one of theOA_* constants fromop.h.
U32 OP_CLASS(OP *o)op_contextualizeApplies a syntactic context to an op tree representing an expression.o is the op tree, andcontext must beG_SCALAR,G_LIST, orG_VOID to specify the context to apply. The modified op tree is returned.
OP * op_contextualize(OP *o, I32 context)op_convert_listConvertso into a list op if it is not one already, and then converts it into the specifiedtype, calling its check function, allocating a target if it needs one, and folding constants.
A list-type op is usually constructed one kid at a time vianewLISTOP,op_prepend_elem andop_append_elem. Then finally it is passed toop_convert_list to make it the right type.
OP * op_convert_list(I32 optype, I32 flags, OP *o)OP_DESCReturn a short description of the provided OP.
const char * OP_DESC(OP *o)op_force_listPromotes o and any siblings to be anOP_LIST if it is not already. If a newOP_LIST op was created, its first child will beOP_PUSHMARK. The returned node itself will be nulled, leaving only its children.
This is often what you want to do before putting the optree into list context; as
o = op_contextualize(op_force_list(o), G_LIST);OP * op_force_list(OP *o)op_freeFree an op and its children. Only use this when an op is no longer linked to from any optree.
Remember that any op withOPf_KIDS set is expected to have a validop_first pointer. If you are attempting to free an op but preserve its child op, make sure to clear that flag before callingop_free(). For example:
OP *kid = o->op_first; o->op_first = NULL;o->op_flags &= ~OPf_KIDS;op_free(o);void op_free(OP *arg)OpHAS_SIBLINGReturns true ifo has a sibling
bool OpHAS_SIBLING(OP *o)OpLASTSIB_setMarkso as having no further siblings and marks o as having the specified parent. See also"OpMORESIB_set" andOpMAYBESIB_set. For a higher-level interface, see"op_sibling_splice".
void OpLASTSIB_set(OP *o, OP *parent)op_linklistThis function is the implementation of the"LINKLIST" macro. It should not be called directly.
OP * op_linklist(OP *o)op_lvalueNOTE:op_lvalue isexperimental and may change or be removed without notice.
Propagate lvalue ("modifiable") context to an op and its children.type represents the context type, roughly based on the type of op that would do the modifying, althoughlocal() is represented byOP_NULL, because it has no op type of its own (it is signalled by a flag on the lvalue op).
This function detects things that can't be modified, such as$x+1, and generates errors for them. For example,$x+1 = 2 would cause it to be called with an op of typeOP_ADD and atype argument ofOP_SASSIGN.
It also flags things that need to behave specially in an lvalue context, such as$$x = 5 which might have to vivify a reference in$x.
OP * op_lvalue(OP *o, I32 type)OpMAYBESIB_setConditionally doesOpMORESIB_set orOpLASTSIB_set depending on whethersib is non-null. For a higher-level interface, see"op_sibling_splice".
void OpMAYBESIB_set(OP *o, OP *sib, OP *parent)OpMORESIB_setSets the sibling ofo to the non-zero valuesib. See also"OpLASTSIB_set" and"OpMAYBESIB_set". For a higher-level interface, see"op_sibling_splice".
void OpMORESIB_set(OP *o, OP *sib)OP_NAMEReturn the name of the provided OP. For core ops this looks up the name from the op_type; for custom ops from the op_ppaddr.
const char * OP_NAME(OP *o)op_nullNeutralizes an op when it is no longer needed, but is still linked to from other ops.
void op_null(OP *o)op_parentReturns the parent OP ofo, if it has a parent. ReturnsNULL otherwise.
OP * op_parent(OP *o)op_prepend_elemPrepend an item to the list of ops contained directly within a list-type op, returning the lengthened list.first is the op to prepend to the list, andlast is the list-type op.optype specifies the intended opcode for the list. Iflast is not already a list of the right type, it will be upgraded into one. If eitherfirst orlast is null, the other is returned unchanged.
OP * op_prepend_elem(I32 optype, OP *first, OP *last)op_scopeNOTE:op_scope isexperimental and may change or be removed without notice.
Wraps up an op tree with some additional ops so that at runtime a dynamic scope will be created. The original ops run in the new dynamic scope, and then, provided that they exit normally, the scope will be unwound. The additional ops used to create and unwind the dynamic scope will normally be anenter/leave pair, but ascope op may be used instead if the ops are simple enough to not need the full dynamic scope structure.
OP * op_scope(OP *o)OpSIBLINGReturns the sibling ofo, orNULL if there is no sibling
OP* OpSIBLING(OP *o)op_sibling_spliceA general function for editing the structure of an existing chain of op_sibling nodes. By analogy with the perl-levelsplice() function, allows you to delete zero or more sequential nodes, replacing them with zero or more different nodes. Performs the necessary op_first/op_last housekeeping on the parent node and op_sibling manipulation on the children. The last deleted node will be marked as the last node by updating the op_sibling/op_sibparent or op_moresib field as appropriate.
Note that op_next is not manipulated, and nodes are not freed; that is the responsibility of the caller. It also won't create a new list op for an empty list etc; use higher-level functions like op_append_elem() for that.
parent is the parent node of the sibling chain. It may passed asNULL if the splicing doesn't affect the first or last op in the chain.
start is the node preceding the first node to be spliced. Node(s) following it will be deleted, and ops will be inserted after it. If it isNULL, the first node onwards is deleted, and nodes are inserted at the beginning.
del_count is the number of nodes to delete. If zero, no nodes are deleted. If -1 or greater than or equal to the number of remaining kids, all remaining kids are deleted.
insert is the first of a chain of nodes to be inserted in place of the nodes. IfNULL, no nodes are inserted.
The head of the chain of deleted ops is returned, orNULL if no ops were deleted.
For example:
action before after returns------ ----- ----- ------- P Psplice(P, A, 2, X-Y-Z) | | B-C A-B-C-D A-X-Y-Z-D P Psplice(P, NULL, 1, X-Y) | | A A-B-C-D X-Y-B-C-D P Psplice(P, NULL, 3, NULL) | | A-B-C A-B-C-D D P Psplice(P, B, 0, X-Y) | | NULL A-B-C-D A-B-X-Y-C-DFor lower-level direct manipulation ofop_sibparent andop_moresib, see"OpMORESIB_set","OpLASTSIB_set","OpMAYBESIB_set".
OP * op_sibling_splice(OP *parent, OP *start, int del_count, OP *insert)optimize_optreeThis function applies some optimisations to the optree in top-down order. It is called before the peephole optimizer, which processes ops in execution order. Note that finalize_optree() also does a top-down scan, but is called *after* the peephole optimizer.
void optimize_optree(OP *o)OP_TYPE_ISReturns true if the given OP is not aNULL pointer and if it is of the given type.
The negation of this macro,OP_TYPE_ISNT is also available as well asOP_TYPE_IS_NN andOP_TYPE_ISNT_NN which elide the NULL pointer check.
bool OP_TYPE_IS(OP *o, Optype type)OP_TYPE_IS_OR_WASReturns true if the given OP is not a NULL pointer and if it is of the given type or used to be before being replaced by an OP of type OP_NULL.
The negation of this macro,OP_TYPE_ISNT_AND_WASNT is also available as well asOP_TYPE_IS_OR_WAS_NN andOP_TYPE_ISNT_AND_WASNT_NN which elide theNULL pointer check.
bool OP_TYPE_IS_OR_WAS(OP *o, Optype type)op_wrap_finallyNOTE:op_wrap_finally isexperimental and may change or be removed without notice.
Wraps the givenblock optree fragment in its own scoped block, arranging for thefinally optree fragment to be invoked when leaving that block for any reason. Both optree fragments are consumed and the combined result is returned.
OP * op_wrap_finally(OP *block, OP *finally)PL_opfreehookWhen non-NULL, the function pointed by this variable will be called each time an OP is freed with the corresponding OP as the argument. This allows extensions to free any extra attribute they have locally attached to an OP. It is also assured to first fire for the parent OP and then for its kids.
When you replace this variable, it is considered a good practice to store the possibly previously installed hook and that you recall it inside your own.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
Perl_ophook_t PL_opfreehookPL_peeppPointer to the per-subroutine peephole optimiser. This is a function that gets called at the end of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform fixups of some ops and to perform small-scale optimisations. The function is called once for each subroutine that is compiled, and is passed, as sole parameter, a pointer to the op that is the entry point to the subroutine. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping the existing optimiser. The basic way to do this can be seen in"Compile pass 3: peephole optimization" in perlguts. If the new code wishes to operate on ops throughout the subroutine's structure, rather than just at the top level, it is likely to be more convenient to wrap the"PL_rpeepp" hook.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
peep_t PL_peeppPL_rpeeppPointer to the recursive peephole optimiser. This is a function that gets called at the end of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform fixups of some ops and to perform small-scale optimisations. The function is called once for each chain of ops linked through theirop_next fields; it is recursively called to handle each side chain. It is passed, as sole parameter, a pointer to the op that is at the head of the chain. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping the existing optimiser. The basic way to do this can be seen in"Compile pass 3: peephole optimization" in perlguts. If the new code wishes to operate only on ops at a subroutine's top level, rather than throughout the structure, it is likely to be more convenient to wrap the"PL_peepp" hook.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
peep_t PL_rpeepprv2cv_op_cvExamines an op, which is expected to identify a subroutine at runtime, and attempts to determine at compile time which subroutine it identifies. This is normally used during Perl compilation to determine whether a prototype can be applied to a function call.cvop is the op being considered, normally anrv2cv op. A pointer to the identified subroutine is returned, if it could be determined statically, and a null pointer is returned if it was not possible to determine statically.
Currently, the subroutine can be identified statically if the RV that therv2cv is to operate on is provided by a suitablegv orconst op. Agv op is suitable if the GV's CV slot is populated. Aconst op is suitable if the constant value must be an RV pointing to a CV. Details of this process may change in future versions of Perl. If therv2cv op has theOPpENTERSUB_AMPER flag set then no attempt is made to identify the subroutine statically: this flag is used to suppress compile-time magic on a subroutine call, forcing it to use default runtime behaviour.
Ifflags has the bitRV2CVOPCV_MARK_EARLY set, then the handling of a GV reference is modified. If a GV was examined and its CV slot was found to be empty, then thegv op has theOPpEARLY_CV flag set. If the op is not optimised away, and the CV slot is later populated with a subroutine having a prototype, that flag eventually triggers the warning "called too early to check prototype".
Ifflags has the bitRV2CVOPCV_RETURN_NAME_GV set, then instead of returning a pointer to the subroutine it returns a pointer to the GV giving the most appropriate name for the subroutine in this context. Normally this is just theCvGV of the subroutine, but for an anonymous (CvANON) subroutine that is referenced through a GV it will be the referencing GV. The resultingGV* is cast toCV* to be returned. A null pointer is returned as usual if there is no statically-determinable subroutine.
CV * rv2cv_op_cv(OP *cvop, U32 flags)packlistThe engine implementingpack() Perl function.
void packlist(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist)unpackstringThe engine implementing theunpack() Perl function.
Using the templatepat..patend, this function unpacks the strings..strend into a number of mortal SVs, which it pushes onto the perl argument (@_) stack (so you will need to issue aPUTBACK before andSPAGAIN after the call to this function). It returns the number of pushed elements.
Thestrend andpatend pointers should point to the byte following the last character of each string.
Although this function returns its values on the perl argument stack, it doesn't take any parameters from that stack (and thus in particular there's no need to do aPUSHMARK before calling it, unlike"call_pv" for example).
SSize_t unpackstring(const char *pat, const char *patend, const char *s, const char *strend, U32 flags)CvPADLISTNOTE:CvPADLIST isexperimental and may change or be removed without notice.
CV's can have CvPADLIST(cv) set to point to a PADLIST. This is the CV's scratchpad, which stores lexical variables and opcode temporary and per-thread values.
For these purposes "formats" are a kind-of CV; eval""s are too (except they're not callable at will and are always thrown away after the eval"" is done executing). Require'd files are simply evals without any outer lexical scope.
XSUBs do not have aCvPADLIST.dXSTARG fetches values fromPL_curpad, but that is really the callers pad (a slot of which is allocated by every entersub). Do not get or setCvPADLIST if a CV is an XSUB (as determined byCvISXSUB()),CvPADLIST slot is reused for a different internal purpose in XSUBs.
The PADLIST has a C array where pads are stored.
The 0th entry of the PADLIST is a PADNAMELIST which represents the "names" or rather the "static type information" for lexicals. The individual elements of a PADNAMELIST are PADNAMEs. Future refactorings might stop the PADNAMELIST from being stored in the PADLIST's array, so don't rely on it. See"PadlistNAMES".
The CvDEPTH'th entry of a PADLIST is a PAD (an AV) which is the stack frame at that depth of recursion into the CV. The 0th slot of a frame AV is an AV which is@_. Other entries are storage for variables and op targets.
Iterating over the PADNAMELIST iterates over all possible pad items. Pad slots for targets (SVs_PADTMP) and GVs end up having &PL_padname_undef "names", while slots for constants have&PL_padname_const "names" (see"pad_alloc"). That&PL_padname_undef and&PL_padname_const are used is an implementation detail subject to change. To test for them, use!PadnamePV(name) andPadnamePV(name) && !PadnameLEN(name), respectively.
Onlymy/our variable slots get valid names. The rest are op targets/GVs/constants which are statically allocated or resolved at compile time. These don't have names by which they can be looked up from Perl code at run time through eval"" the waymy/our variables can be. Since they can't be looked up by "name" but only by their index allocated at compile time (which is usually inPL_op->op_targ), wasting a name SV for them doesn't make sense.
The pad names in the PADNAMELIST have their PV holding the name of the variable. TheCOP_SEQ_RANGE_LOW and_HIGH fields form a range (low+1..high inclusive) of cop_seq numbers for which the name is valid. During compilation, these fields may hold the special value PERL_PADSEQ_INTRO to indicate various stages:
COP_SEQ_RANGE_LOW _HIGH----------------- -----PERL_PADSEQ_INTRO 0 variable not yet introduced: { my ($xvalid-seq# PERL_PADSEQ_INTRO variable in scope: { my ($x);valid-seq# valid-seq# compilation of scope complete: { my ($x); .... }When a lexical var hasn't yet been introduced, it already exists from the perspective of duplicate declarations, but not for variable lookups, e.g.
my ($x, $x); # '"my" variable $x masks earlier declaration'my $x = $x; # equal to my $x = $::x;For typed lexicalsPadnameTYPE points at the type stash. Forour lexicals,PadnameOURSTASH points at the stash of the associated global (so that duplicateour declarations in the same package can be detected).PadnameGEN is sometimes used to store the generation number during compilation.
IfPadnameOUTER is set on the pad name, then that slot in the frame AV is a REFCNT'ed reference to a lexical from "outside". Such entries are sometimes referred to as 'fake'. In this case, the name does not use 'low' and 'high' to store a cop_seq range, since it is in scope throughout. Instead 'high' stores some flags containing info about the real lexical (is it declared in an anon, and is it capable of being instantiated multiple times?), and for fake ANONs, 'low' contains the index within the parent's pad where the lexical's value is stored, to make cloning quicker.
If the 'name' is& the corresponding entry in the PAD is a CV representing a possible closure.
Note that formats are treated as anon subs, and are cloned each time write is called (if necessary).
The flagSVs_PADSTALE is cleared on lexicals each time themy() is executed, and set on scope exit. This allows the"Variable $x is not available" warning to be generated in evals, such as
{ my $x = 1; sub f { eval '$x'} } f();For state vars,SVs_PADSTALE is overloaded to mean 'not yet initialised', but this internal state is stored in a separate pad entry.
PADLIST * CvPADLIST(CV *cv)pad_add_name_pvsExactly like"pad_add_name_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_add_name_pvs("name", U32 flags, HV *typestash, HV *ourstash)PadARRAYNOTE:PadARRAY isexperimental and may change or be removed without notice.
The C array of pad entries.
SV ** PadARRAY(PAD * pad)pad_findmy_pvsExactly like"pad_findmy_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_findmy_pvs("name", U32 flags)PadlistARRAYNOTE:PadlistARRAY isexperimental and may change or be removed without notice.
The C array of a padlist, containing the pads. Only subscript it with numbers >= 1, as the 0th entry is not guaranteed to remain usable.
PAD ** PadlistARRAY(PADLIST * padlist)PadlistMAXNOTE:PadlistMAX isexperimental and may change or be removed without notice.
The index of the last allocated space in the padlist. Note that the last pad may be in an earlier slot. Any entries following it will beNULL in that case.
SSize_t PadlistMAX(PADLIST * padlist)PadlistNAMESNOTE:PadlistNAMES isexperimental and may change or be removed without notice.
The names associated with pad entries.
PADNAMELIST * PadlistNAMES(PADLIST * padlist)PadlistNAMESARRAYNOTE:PadlistNAMESARRAY isexperimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadlistNAMESARRAY(PADLIST * padlist)PadlistNAMESMAXNOTE:PadlistNAMESMAX isexperimental and may change or be removed without notice.
The index of the last pad name.
SSize_t PadlistNAMESMAX(PADLIST * padlist)PadlistREFCNTNOTE:PadlistREFCNT isexperimental and may change or be removed without notice.
The reference count of the padlist. Currently this is always 1.
U32 PadlistREFCNT(PADLIST * padlist)PadMAXNOTE:PadMAX isexperimental and may change or be removed without notice.
The index of the last pad entry.
SSize_t PadMAX(PAD * pad)PadnameLENNOTE:PadnameLEN isexperimental and may change or be removed without notice.
The length of the name.
STRLEN PadnameLEN(PADNAME * pn)PadnamelistARRAYNOTE:PadnamelistARRAY isexperimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadnamelistARRAY(PADNAMELIST * pnl)PadnamelistMAXNOTE:PadnamelistMAX isexperimental and may change or be removed without notice.
The index of the last pad name.
SSize_t PadnamelistMAX(PADNAMELIST * pnl)PadnamelistREFCNTNOTE:PadnamelistREFCNT isexperimental and may change or be removed without notice.
The reference count of the pad name list.
SSize_t PadnamelistREFCNT(PADNAMELIST * pnl)PadnamelistREFCNT_decNOTE:PadnamelistREFCNT_dec isexperimental and may change or be removed without notice.
Lowers the reference count of the pad name list.
void PadnamelistREFCNT_dec(PADNAMELIST * pnl)PadnamePVNOTE:PadnamePV isexperimental and may change or be removed without notice.
The name stored in the pad name struct. This returnsNULL for a target slot.
char * PadnamePV(PADNAME * pn)PadnameREFCNTNOTE:PadnameREFCNT isexperimental and may change or be removed without notice.
The reference count of the pad name.
SSize_t PadnameREFCNT(PADNAME * pn)PadnameREFCNT_decNOTE:PadnameREFCNT_dec isexperimental and may change or be removed without notice.
Lowers the reference count of the pad name.
void PadnameREFCNT_dec(PADNAME * pn)PadnameREFCNT_incNOTE:PadnameREFCNT_inc isexperimental and may change or be removed without notice.
Increases the reference count of the pad name. Returns the pad name itself.
PADNAME * PadnameREFCNT_inc(PADNAME * pn)PadnameSVNOTE:PadnameSV isexperimental and may change or be removed without notice.
Returns the pad name as a mortal SV.
SV * PadnameSV(PADNAME * pn)PadnameUTF8NOTE:PadnameUTF8 isexperimental and may change or be removed without notice.
Whether PadnamePV is in UTF-8. Currently, this is always true.
bool PadnameUTF8(PADNAME * pn)pad_newCreate a new padlist, updating the global variables for the currently-compiling padlist to point to the new padlist. The following flags can be OR'ed together:
padnew_CLONEthis pad is for a cloned CVpadnew_SAVEsave old globals on the save stackpadnew_SAVESUBalso save extra stuff for start of subPADLIST * pad_new(int flags)PL_comppadNOTE:PL_comppad isexperimental and may change or be removed without notice.
During compilation, this points to the array containing the values part of the pad for the currently-compiling code. (At runtime a CV may have many such value arrays; at compile time just one is constructed.) At runtime, this points to the array containing the currently-relevant values for the pad for the currently-executing code.
PL_comppad_nameNOTE:PL_comppad_name isexperimental and may change or be removed without notice.
During compilation, this points to the array containing the names part of the pad for the currently-compiling code.
PL_curpadNOTE:PL_curpad isexperimental and may change or be removed without notice.
Points directly to the body of the"PL_comppad" array. (I.e., this isPadARRAY(PL_comppad).)
SVs_PADMYDEPRECATED! It is planned to removeSVs_PADMY from a future release of Perl. Do not use it for new code; remove it from existing code.
Described inperlguts.
GRPASSWDThis symbol, if defined, indicates to the C program thatstruct group ingrp.h containsgr_passwd.
HAS_ENDGRENTThis symbol, if defined, indicates that the getgrent routine is available for finalizing sequential access of the group database.
HAS_ENDGRENT_RThis symbol, if defined, indicates that theendgrent_r routine is available to endgrent re-entrantly.
HAS_ENDPWENTThis symbol, if defined, indicates that theendpwent routine is available for finalizing sequential access of the passwd database.
HAS_ENDPWENT_RThis symbol, if defined, indicates that theendpwent_r routine is available to endpwent re-entrantly.
HAS_GETGRENTThis symbol, if defined, indicates that thegetgrent routine is available for sequential access of the group database.
HAS_GETGRENT_RThis symbol, if defined, indicates that thegetgrent_r routine is available to getgrent re-entrantly.
HAS_GETPWENTThis symbol, if defined, indicates that thegetpwent routine is available for sequential access of the passwd database. If this is not available, the oldergetpw() function may be available.
HAS_GETPWENT_RThis symbol, if defined, indicates that thegetpwent_r routine is available to getpwent re-entrantly.
HAS_SETGRENTThis symbol, if defined, indicates that thesetgrent routine is available for initializing sequential access of the group database.
HAS_SETGRENT_RThis symbol, if defined, indicates that thesetgrent_r routine is available to setgrent re-entrantly.
HAS_SETPWENTThis symbol, if defined, indicates that thesetpwent routine is available for initializing sequential access of the passwd database.
HAS_SETPWENT_RThis symbol, if defined, indicates that thesetpwent_r routine is available to setpwent re-entrantly.
PWAGEThis symbol, if defined, indicates to the C program thatstruct passwd containspw_age.
PWCHANGEThis symbol, if defined, indicates to the C program thatstruct passwd containspw_change.
PWCLASSThis symbol, if defined, indicates to the C program thatstruct passwd containspw_class.
PWCOMMENTThis symbol, if defined, indicates to the C program thatstruct passwd containspw_comment.
PWEXPIREThis symbol, if defined, indicates to the C program thatstruct passwd containspw_expire.
PWGECOSThis symbol, if defined, indicates to the C program thatstruct passwd containspw_gecos.
PWPASSWDThis symbol, if defined, indicates to the C program thatstruct passwd containspw_passwd.
PWQUOTAThis symbol, if defined, indicates to the C program thatstruct passwd containspw_quota.
CSHThis symbol, if defined, contains the full pathname of csh.
LOC_SEDThis symbol holds the complete pathname to the sed program.
SH_PATHThis symbol contains the full pathname to the shell used on this on this system to execute Bourne shell scripts. Usually, this will be/bin/sh, though it's possible that some systems will have/bin/ksh,/bin/pdksh,/bin/ash,/bin/bash, or even something such as D:/bin/sh.exe.
CRYPT_R_PROTOThis symbol encodes the prototype ofcrypt_r. It is zero ifd_crypt_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_crypt_r is defined.
CTERMID_R_PROTOThis symbol encodes the prototype ofctermid_r. It is zero ifd_ctermid_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_ctermid_r is defined.
DRAND48_R_PROTOThis symbol encodes the prototype ofdrand48_r. It is zero ifd_drand48_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_drand48_r is defined.
ENDGRENT_R_PROTOThis symbol encodes the prototype ofendgrent_r. It is zero ifd_endgrent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_endgrent_r is defined.
ENDHOSTENT_R_PROTOThis symbol encodes the prototype ofendhostent_r. It is zero ifd_endhostent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_endhostent_r is defined.
ENDNETENT_R_PROTOThis symbol encodes the prototype ofendnetent_r. It is zero ifd_endnetent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_endnetent_r is defined.
ENDPROTOENT_R_PROTOThis symbol encodes the prototype ofendprotoent_r. It is zero ifd_endprotoent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_endprotoent_r is defined.
ENDPWENT_R_PROTOThis symbol encodes the prototype ofendpwent_r. It is zero ifd_endpwent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_endpwent_r is defined.
ENDSERVENT_R_PROTOThis symbol encodes the prototype ofendservent_r. It is zero ifd_endservent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_endservent_r is defined.
GDBMNDBM_H_USES_PROTOTYPESThis symbol, if defined, indicates thatgdbm/ndbm.h uses realANSI C prototypes instead of K&R style function declarations without any parameter information. WhileANSI C prototypes are supported in C++, K&R style function declarations will yield errors.
GDBM_NDBM_H_USES_PROTOTYPESThis symbol, if defined, indicates that <gdbm-ndbm.h> uses realANSI C prototypes instead of K&R style function declarations without any parameter information. WhileANSI C prototypes are supported in C++, K&R style function declarations will yield errors.
GETGRENT_R_PROTOThis symbol encodes the prototype ofgetgrent_r. It is zero ifd_getgrent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getgrent_r is defined.
GETGRGID_R_PROTOThis symbol encodes the prototype ofgetgrgid_r. It is zero ifd_getgrgid_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getgrgid_r is defined.
GETGRNAM_R_PROTOThis symbol encodes the prototype ofgetgrnam_r. It is zero ifd_getgrnam_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getgrnam_r is defined.
GETHOSTBYADDR_R_PROTOThis symbol encodes the prototype ofgethostbyaddr_r. It is zero ifd_gethostbyaddr_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_gethostbyaddr_r is defined.
GETHOSTBYNAME_R_PROTOThis symbol encodes the prototype ofgethostbyname_r. It is zero ifd_gethostbyname_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_gethostbyname_r is defined.
GETHOSTENT_R_PROTOThis symbol encodes the prototype ofgethostent_r. It is zero ifd_gethostent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_gethostent_r is defined.
GETLOGIN_R_PROTOThis symbol encodes the prototype ofgetlogin_r. It is zero ifd_getlogin_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getlogin_r is defined.
GETNETBYADDR_R_PROTOThis symbol encodes the prototype ofgetnetbyaddr_r. It is zero ifd_getnetbyaddr_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getnetbyaddr_r is defined.
GETNETBYNAME_R_PROTOThis symbol encodes the prototype ofgetnetbyname_r. It is zero ifd_getnetbyname_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getnetbyname_r is defined.
GETNETENT_R_PROTOThis symbol encodes the prototype ofgetnetent_r. It is zero ifd_getnetent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getnetent_r is defined.
GETPROTOBYNAME_R_PROTOThis symbol encodes the prototype ofgetprotobyname_r. It is zero ifd_getprotobyname_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getprotobyname_r is defined.
GETPROTOBYNUMBER_R_PROTOThis symbol encodes the prototype ofgetprotobynumber_r. It is zero ifd_getprotobynumber_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getprotobynumber_r is defined.
GETPROTOENT_R_PROTOThis symbol encodes the prototype ofgetprotoent_r. It is zero ifd_getprotoent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getprotoent_r is defined.
GETPWENT_R_PROTOThis symbol encodes the prototype ofgetpwent_r. It is zero ifd_getpwent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getpwent_r is defined.
GETPWNAM_R_PROTOThis symbol encodes the prototype ofgetpwnam_r. It is zero ifd_getpwnam_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getpwnam_r is defined.
GETPWUID_R_PROTOThis symbol encodes the prototype ofgetpwuid_r. It is zero ifd_getpwuid_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getpwuid_r is defined.
GETSERVBYNAME_R_PROTOThis symbol encodes the prototype ofgetservbyname_r. It is zero ifd_getservbyname_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getservbyname_r is defined.
GETSERVBYPORT_R_PROTOThis symbol encodes the prototype ofgetservbyport_r. It is zero ifd_getservbyport_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getservbyport_r is defined.
GETSERVENT_R_PROTOThis symbol encodes the prototype ofgetservent_r. It is zero ifd_getservent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getservent_r is defined.
GETSPNAM_R_PROTOThis symbol encodes the prototype ofgetspnam_r. It is zero ifd_getspnam_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_getspnam_r is defined.
HAS_DBMINIT_PROTOThis symbol, if defined, indicates that the system provides a prototype for thedbminit() function. Otherwise, it is up to the program to supply one. A good guess is
extern int dbminit(char *);HAS_DRAND48_PROTOThis symbol, if defined, indicates that the system provides a prototype for thedrand48() function. Otherwise, it is up to the program to supply one. A good guess is
extern double drand48(void);HAS_FLOCK_PROTOThis symbol, if defined, indicates that the system provides a prototype for theflock() function. Otherwise, it is up to the program to supply one. A good guess is
extern int flock(int, int);HAS_GETHOST_PROTOSThis symbol, if defined, indicates thatnetdb.h includes prototypes forgethostent(),gethostbyname(), andgethostbyaddr(). Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for variousNetdb_xxx_t types.
HAS_GETNET_PROTOSThis symbol, if defined, indicates thatnetdb.h includes prototypes forgetnetent(),getnetbyname(), andgetnetbyaddr(). Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for variousNetdb_xxx_t types.
HAS_GETPROTO_PROTOSThis symbol, if defined, indicates thatnetdb.h includes prototypes forgetprotoent(),getprotobyname(), andgetprotobyaddr(). Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for variousNetdb_xxx_t types.
HAS_GETSERV_PROTOSThis symbol, if defined, indicates thatnetdb.h includes prototypes forgetservent(),getservbyname(), andgetservbyaddr(). Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for variousNetdb_xxx_t types.
HAS_MODFL_PROTOThis symbol, if defined, indicates that the system provides a prototype for themodfl() function. Otherwise, it is up to the program to supply one.
HAS_SBRK_PROTOThis symbol, if defined, indicates that the system provides a prototype for thesbrk() function. Otherwise, it is up to the program to supply one. Good guesses are
extern void* sbrk(int);extern void* sbrk(size_t);HAS_SETRESGID_PROTOThis symbol, if defined, indicates that the system provides a prototype for thesetresgid() function. Otherwise, it is up to the program to supply one. Good guesses are
extern int setresgid(uid_t ruid, uid_t euid, uid_t suid);HAS_SETRESUID_PROTOThis symbol, if defined, indicates that the system provides a prototype for thesetresuid() function. Otherwise, it is up to the program to supply one. Good guesses are
extern int setresuid(uid_t ruid, uid_t euid, uid_t suid);HAS_SHMAT_PROTOTYPEThis symbol, if defined, indicates that thesys/shm.h includes a prototype forshmat(). Otherwise, it is up to the program to guess one.Shmat_tshmat(int, Shmat_t, int) is a good guess, but not always right so it should be emitted by the program only whenHAS_SHMAT_PROTOTYPE is not defined to avoid conflicting defs.
HAS_SOCKATMARK_PROTOThis symbol, if defined, indicates that the system provides a prototype for thesockatmark() function. Otherwise, it is up to the program to supply one. A good guess is
extern int sockatmark(int);HAS_SYSCALL_PROTOThis symbol, if defined, indicates that the system provides a prototype for thesyscall() function. Otherwise, it is up to the program to supply one. Good guesses are
extern int syscall(int, ...);extern int syscall(long, ...);HAS_TELLDIR_PROTOThis symbol, if defined, indicates that the system provides a prototype for thetelldir() function. Otherwise, it is up to the program to supply one. A good guess is
extern long telldir(DIR*);NDBM_H_USES_PROTOTYPESThis symbol, if defined, indicates thatndbm.h uses realANSI C prototypes instead of K&R style function declarations without any parameter information. WhileANSI C prototypes are supported in C++, K&R style function declarations will yield errors.
RANDOM_R_PROTOThis symbol encodes the prototype ofrandom_r. It is zero ifd_random_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_random_r is defined.
READDIR_R_PROTOThis symbol encodes the prototype ofreaddir_r. It is zero ifd_readdir_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_readdir_r is defined.
SETGRENT_R_PROTOThis symbol encodes the prototype ofsetgrent_r. It is zero ifd_setgrent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_setgrent_r is defined.
SETHOSTENT_R_PROTOThis symbol encodes the prototype ofsethostent_r. It is zero ifd_sethostent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_sethostent_r is defined.
SETLOCALE_R_PROTOThis symbol encodes the prototype ofsetlocale_r. It is zero ifd_setlocale_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_setlocale_r is defined.
SETNETENT_R_PROTOThis symbol encodes the prototype ofsetnetent_r. It is zero ifd_setnetent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_setnetent_r is defined.
SETPROTOENT_R_PROTOThis symbol encodes the prototype ofsetprotoent_r. It is zero ifd_setprotoent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_setprotoent_r is defined.
SETPWENT_R_PROTOThis symbol encodes the prototype ofsetpwent_r. It is zero ifd_setpwent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_setpwent_r is defined.
SETSERVENT_R_PROTOThis symbol encodes the prototype ofsetservent_r. It is zero ifd_setservent_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_setservent_r is defined.
SRANDOM_R_PROTOThis symbol encodes the prototype ofsrandom_r. It is zero ifd_srandom_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_srandom_r is defined.
SRAND48_R_PROTOThis symbol encodes the prototype ofsrand48_r. It is zero ifd_srand48_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_srand48_r is defined.
STRERROR_R_PROTOThis symbol encodes the prototype ofstrerror_r. It is zero ifd_strerror_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_strerror_r is defined.
TMPNAM_R_PROTOThis symbol encodes the prototype oftmpnam_r. It is zero ifd_tmpnam_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_tmpnam_r is defined.
TTYNAME_R_PROTOThis symbol encodes the prototype ofttyname_r. It is zero ifd_ttyname_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_ttyname_r is defined.
Functions for pushing and pulling items on the stack when the stack is reference counted. They are intended as replacements for the old PUSHs, POPi, EXTEND etc pp macros within pp functions.
rpp_contextNOTE:rpp_context isexperimental and may change or be removed without notice.
Impose void, scalar or list context on the stack. First, popextra items off the stack, then whengimme is:G_LIST: return as-is.G_VOID: pop everything back tomarkG_SCALAR: move the top stack item (or&PL_sv_undef if none) tomark+1 and free everything above it.
void rpp_context(SV **mark, U8 gimme, SSize_t extra)rpp_extendNOTE:rpp_extend isexperimental and may change or be removed without notice.
Ensures that there is space on the stack to pushn items, extending it if necessary.
void rpp_extend(SSize_t n)rpp_invoke_xsNOTE:rpp_invoke_xs isexperimental and may change or be removed without notice.
Call the XS function associated withcv. Wraps the call if necessary to handle XS functions which are not aware of reference-counted stacks.
void rpp_invoke_xs(CV *cv)rpp_is_loneNOTE:rpp_is_lone isexperimental and may change or be removed without notice.
Indicates whether the stacked SVsv (assumed to be not yet popped off the stack) is only kept alive due to a single reference from the argument stack and/or and the temps stack.
This can used for example to decide whether the copying of return values in rvalue context can be skipped, or whether it shouldn't be assigned to in lvalue context.
bool rpp_is_lone(SV *sv)rpp_popfree_1_NNNOTE:rpp_popfree_1_NN isexperimental and may change or be removed without notice.
A variant of rpp_popfree_1() which assumes that the pointer being popped off the stack is non-NULL.
void rpp_popfree_1_NN()rpp_popfree_2_NNNOTE:rpp_popfree_2_NN isexperimental and may change or be removed without notice.
A variant of rpp_popfree_2() which assumes that the two pointers being popped off the stack are non-NULL.
void rpp_popfree_2_NN()rpp_popfree_toNOTE:rpp_popfree_to isexperimental and may change or be removed without notice.
Pop and free all items on the argument stack abovesp. On return,PL_stack_sp will be equal tosp.
void rpp_popfree_to(SV **sp)rpp_popfree_to_NNNOTE:rpp_popfree_to_NN isexperimental and may change or be removed without notice.
A variant of rpp_popfree_to() which assumes that all the pointers being popped off the stack are non-NULL.
void rpp_popfree_to_NN(SV **sp)rpp_popfree_1NOTE:rpp_popfree_1 isexperimental and may change or be removed without notice.
Pop and free the top item on the argument stack and updatePL_stack_sp.
void rpp_popfree_1()rpp_popfree_2NOTE:rpp_popfree_2 isexperimental and may change or be removed without notice.
Pop and free the top two items on the argument stack and updatePL_stack_sp.
void rpp_popfree_2()rpp_pop_1_norcNOTE:rpp_pop_1_norc isexperimental and may change or be removed without notice.
Pop and return the top item off the argument stack and updatePL_stack_sp. It's similar to rpp_popfree_1(), except that it actually returns a value, and itdoesn't decrement the SV's reference count. On non-PERL_RC_STACK builds it actually increments the SV's reference count.
This is useful in cases where the popped value is immediately embedded somewhere e.g. via av_store(), allowing you skip decrementing and then immediately incrementing the reference count again (and risk prematurely freeing the SV if it had a RC of 1). On non-RC builds, the reference count bookkeeping still works too, which is why it should be used rather than a simple*PL_stack_sp--.
SV * rpp_pop_1_norc()rpp_push_1_norcNOTE:rpp_push_1_norc isexperimental and may change or be removed without notice.
Pushsv onto the stack without incrementing its reference count, and updatePL_stack_sp. On non-PERL_RC_STACK builds, mortalise too.
This is most useful where an SV has just been created and already has a reference count of 1, but has not yet been anchored anywhere.
void rpp_push_1_norc(SV *sv)rpp_push_1rpp_push_IMMrpp_push_2rpp_xpush_1rpp_xpush_IMMrpp_xpush_2NOTE: all these forms areexperimental and may change or be removed without notice.
Push one or two SVs onto the stack, incrementing their reference counts and updatingPL_stack_sp. With thex variants, it extends the stack first. TheIMM variants assume that the single argument is an immortal such as <&PL_sv_undef> and, for efficiency, will skip incrementing its reference count.
void rpp_push_1 (SV *sv)void rpp_push_IMM (SV *sv)void rpp_push_2 (SV *sv1, SV *sv2)void rpp_xpush_1 (SV *sv)void rpp_xpush_IMM(SV *sv)void rpp_xpush_2 (SV *sv1, SV *sv2)rpp_replace_atNOTE:rpp_replace_at isexperimental and may change or be removed without notice.
Replace the SV at address sp within the stack withsv, while suitably adjusting reference counts. Equivalent to*sp = sv, except with proper reference count handling.
void rpp_replace_at(SV **sp, SV *sv)rpp_replace_at_NNNOTE:rpp_replace_at_NN isexperimental and may change or be removed without notice.
A variant of rpp_replace_at() which assumes that the SV pointer on the stack is non-NULL.
void rpp_replace_at_NN(SV **sp, SV *sv)rpp_replace_at_norcNOTE:rpp_replace_at_norc isexperimental and may change or be removed without notice.
Replace the SV at address sp within the stack withsv, while suitably adjusting the reference count of the old SV. Equivalent to*sp = sv, except with proper reference count handling.
sv's reference count doesn't get incremented. On non-PERL_RC_STACK builds, it gets mortalised too.
This is most useful where an SV has just been created and already has a reference count of 1, but has not yet been anchored anywhere.
void rpp_replace_at_norc(SV **sp, SV *sv)rpp_replace_at_norc_NNNOTE:rpp_replace_at_norc_NN isexperimental and may change or be removed without notice.
A variant of rpp_replace_at_norc() which assumes that the SV pointer on the stack is non-NULL.
void rpp_replace_at_norc_NN(SV **sp, SV *sv)rpp_replace_1_1rpp_replace_1_1_NNrpp_replace_1_IMM_NNNOTE: all these forms areexperimental and may change or be removed without notice.
Replace the current top stack item withsv, while suitably adjusting reference counts. Equivalent to rpp_popfree_1(); rpp_push_1(sv), but is more efficient and handles both SVs being the same.
The_NN variant assumes that the pointer on the stack to the SV being freed is non-NULL.
TheIMM_NN variant is like the_NN variant, but in addition, assumes that the single argument is an immortal such as <&PL_sv_undef> and, for efficiency, will skip incrementing its reference count.
void rpp_replace_1_1(SV *sv)rpp_replace_2_1rpp_replace_2_1_NNrpp_replace_2_IMM_NNNOTE: all these forms areexperimental and may change or be removed without notice.
Replace the current top to stacks item withsv, while suitably adjusting reference counts. Equivalent to rpp_popfree_2(); rpp_push_1(sv), but is more efficient and handles SVs being the same.
The_NN variant assumes that the pointers on the stack to the SVs being freed are non-NULL.
TheIMM_NN variant is like the_NN variant, but in addition, assumes that the single argument is an immortal such as <&PL_sv_undef> and, for efficiency, will skip incrementing its reference count.
void rpp_replace_2_1(SV *sv)rpp_stack_is_rcNOTE:rpp_stack_is_rc isexperimental and may change or be removed without notice.
Returns a boolean value indicating whether the stack is currently reference-counted. Note that if the stack is split (bottom half RC, top half non-RC), this function returns false, even if the top half currently contains zero items.
bool rpp_stack_is_rc()rpp_try_AMAGIC_1rpp_try_AMAGIC_2NOTE: both forms areexperimental and may change or be removed without notice.
Check whether either of the one or two SVs at the top of the stack is magical or a ref, and in either case handle it specially: invoke get magic, call an overload method, or replace a ref with a temporary numeric value, as appropriate. If this function returns true, it indicates that the correct return value is already on the stack. Intended to be used at the beginning of the PP function for unary or binary ops.
bool rpp_try_AMAGIC_1(int method, int flags)XSPP_wrappedNOTE:XSPP_wrapped isexperimental and may change or be removed without notice.
Declare and wrap a non-reference-counted PP-style function. On traditional perl builds where the stack isn't reference-counted, this just produces a function declaration like
OP * xsppw_name(pTHX)Conversely, in ref-counted builds it creates xsppw_name() as a small wrapper function which calls the real function via a wrapper which processes the args and return values to ensure that reference counts are properly handled for code which uses old-style dSP, PUSHs(), POPs() etc, which don't adjust the reference counts of the items they manipulate.
xsppw_nargs indicates how many arguments the function consumes off the stack. It can be a constant value or an expression, such as
((PL_op->op_flags & OPf_STACKED) ? 2 : 1)Alternatively if xsppw_nlists is 1, it indicates that the PP function consumes a list (or - rarely - if 2, consumes two lists, like pp_aassign()), as indicated by the top markstack position.
This is intended as a temporary fix when converting XS code to run under PERL_RC_STACK builds. In the longer term, the PP function should be rewritten to replace PUSHs() etc with rpp_push_1() etc.
XSPP_wrapped(xsppw_name, I32 xsppw_nargs, I32 xsppw_nlists)pregcompDescribed inperlreguts.
REGEXP * pregcomp(SV * const pattern, const U32 flags)pregexecDescribed inperlreguts.
I32 pregexec(REGEXP * const prog, char *stringarg, char *strend, char *strbeg, SSize_t minend, SV *screamer, U32 nosave)re_compileCompile the regular expression patternpattern, returning a pointer to the compiled object for later matching with the internal regex engine.
This function is typically used by a custom regexp engine.comp() function to hand off to the core regexp engine those patterns it doesn't want to handle itself (typically passing through the same flags it was called with). In almost all other cases, a regexp should be compiled by calling"pregcomp" to compile using the currently active regexp engine.
Ifpattern is already aREGEXP, this function does nothing but return a pointer to the input. Otherwise the PV is extracted and treated like a string representing a pattern. Seeperlre.
The possible flags forrx_flags are documented inperlreapi. Their names all begin withRXf_.
REGEXP * re_compile(SV * const pattern, U32 orig_rx_flags)re_dup_gutsDuplicate a regexp.
This routine is expected to clone a given regexp structure. It is only compiled under USE_ITHREADS.
After all of the core data stored in struct regexp is duplicated theregexp_engine.dupe method is used to copy any private data stored in the *pprivate pointer. This allows extensions to handle any duplication they need to do.
void re_dup_guts(const REGEXP *sstr, REGEXP *dstr, CLONE_PARAMS *param)regexp_engineWhen a regexp is compiled, itsengine field is then set to point at the appropriate structure, so that when it needs to be used Perl can find the right routines to do so.
In order to install a new regexp handler,$^H{regcomp} is set to an integer which (when casted appropriately) resolves to one of these structures. When compiling, thecomp method is executed, and the resultingregexp structure's engine field is expected to point back at the same structure.
The pTHX_ symbol in the definition is a macro used by Perl under threading to provide an extra argument to the routine holding a pointer back to the interpreter that is executing the regexp. So under threading all routines get an extra argument.
regmatch_infoSome basic information about the current match that is created by Perl_regexec_flags and then passed to regtry(), regmatch() etc. It is allocated as a local var on the stack, so nothing should be stored in it that needs preserving or clearing up on croak(). For that, see the aux_info and aux_info_eval members of the regmatch_state union.
RXapif_ALLRXapif_CLEARRXapif_DELETERXapif_EXISTSRXapif_FETCHRXapif_FIRSTKEYRXapif_NEXTKEYRXapif_ONERXapif_REGNAMERXapif_REGNAMESRXapif_REGNAMES_COUNTRXapif_SCALARRXapif_STOREDescribed inperlreapi.
RX_BUFF_IDX_CARET_FULLMATCHRX_BUFF_IDX_CARET_POSTMATCHRX_BUFF_IDX_CARET_PREMATCHRX_BUFF_IDX_FULLMATCHRX_BUFF_IDX_POSTMATCHRX_BUFF_IDX_PREMATCHDescribed inperlreapi.
RXf_NO_INPLACE_SUBSTRXf_NULLRXf_SKIPWHITERXf_SPLITRXf_START_ONLYRXf_WHITEDescribed inperlreapi.
RXf_PMf_EXTENDEDRXf_PMf_FOLDRXf_PMf_KEEPCOPYRXf_PMf_MULTILINERXf_PMf_SINGLELINEDescribed inperlreapi.
SvRXConvenience macro to get the REGEXP from a SV. This is approximately equivalent to the following snippet:
if (SvMAGICAL(sv)) mg_get(sv);if (SvROK(sv)) sv = MUTABLE_SV(SvRV(sv));if (SvTYPE(sv) == SVt_REGEXP) return (REGEXP*) sv;NULL will be returned if a REGEXP* is not found.
REGEXP * SvRX(SV *sv)SvRXOKReturns a boolean indicating whether the SV (or the one it references) is a REGEXP.
If you want to do something with the REGEXP* later use SvRX instead and check for NULL.
bool SvRXOK(SV* sv)These are used in the simple report generation feature of Perl. Seeperlform.
HAS_SIGINFO_SI_ADDRThis symbol, if defined, indicates thatsiginfo_t has thesi_addr member
HAS_SIGINFO_SI_BANDThis symbol, if defined, indicates thatsiginfo_t has thesi_band member
HAS_SIGINFO_SI_ERRNOThis symbol, if defined, indicates thatsiginfo_t has thesi_errno member
HAS_SIGINFO_SI_PIDThis symbol, if defined, indicates thatsiginfo_t has thesi_pid member
HAS_SIGINFO_SI_STATUSThis symbol, if defined, indicates thatsiginfo_t has thesi_status member
HAS_SIGINFO_SI_UIDThis symbol, if defined, indicates thatsiginfo_t has thesi_uid member
HAS_SIGINFO_SI_VALUEThis symbol, if defined, indicates thatsiginfo_t has thesi_value member
PERL_SIGNALS_UNSAFE_FLAGIf this bit inPL_signals is set, the system is uing the pre-Perl 5.8 unsafe signals. See"PERL_SIGNALS" in perlrun and"Deferred Signals (Safe Signals)" in perlipc.
U32 PERL_SIGNALS_UNSAFE_FLAGrsignalA wrapper for the C library functionssigaction(2) orsignal(2). Use this instead of those libc functions, as the Perl version gives the safest available implementation, and knows things that interact with the rest of the perl interpreter.
Sighandler_t rsignal(int i, Sighandler_t t)rsignal_stateReturns a the current signal handler for signalsigno. See"rsignal".
Sighandler_t rsignal_state(int i)Sigjmp_bufThis is the buffer type to be used with Sigsetjmp and Siglongjmp.
SiglongjmpThis macro is used in the same way assiglongjmp(), but will invoke traditionallongjmp() if siglongjmp isn't available. See"HAS_SIGSETJMP".
void Siglongjmp(jmp_buf env, int val)SIG_NAMEThis symbol contains a list of signal names in order of signal number. This is intended to be used as a static array initialization, like this:
char *sig_name[] = { SIG_NAME };The signals in the list are separated with commas, and each signal is surrounded by double quotes. There is no leadingSIG in the signal name, i.e.SIGQUIT is known as "QUIT". Gaps in the signal numbers (up toNSIG) are filled in withNUMnn, etc., where nn is the actual signal number (e.g.NUM37). The signal number forsig_name[i] is stored insig_num[i]. The last element is 0 to terminate the list with aNULL. This corresponds to the 0 at the end of thesig_name_init list. Note that this variable is initialized from thesig_name_init, not fromsig_name (which is unused).
SIG_NUMThis symbol contains a list of signal numbers, in the same order as theSIG_NAME list. It is suitable for static array initialization, as in:
int sig_num[] = { SIG_NUM };The signals in the list are separated with commas, and the indices within that list and theSIG_NAME list match, so it's easy to compute the signal name from a number or vice versa at the price of a small dynamic linear lookup. Duplicates are allowed, but are moved to the end of the list. The signal number corresponding tosig_name[i] issig_number[i]. if (i <NSIG) thensig_number[i] == i. The last element is 0, corresponding to the 0 at the end of thesig_name_init list. Note that this variable is initialized from thesig_num_init, not fromsig_num (which is unused).
SigsetjmpThis macro is used in the same way assigsetjmp(), but will invoke traditionalsetjmp() if sigsetjmp isn't available. See"HAS_SIGSETJMP".
int Sigsetjmp(jmp_buf env, int savesigs)SIG_SIZEThis variable contains the number of elements of theSIG_NAME andSIG_NUM arrays, excluding the finalNULL entry.
whichsigwhichsig_pvwhichsig_pvnwhichsig_svThese all convert a signal name into its corresponding signal number; returning -1 if no corresponding number was found.
They differ only in the source of the signal name:
whichsig_pv takes the name from theNUL-terminated string starting atsig.
whichsig is merely a different spelling, a synonym, ofwhichsig_pv.
whichsig_pvn takes the name from the string starting atsig, with lengthlen bytes.
whichsig_sv takes the name from the PV stored in the SVsigsv.
I32 whichsig (const char *sig)I32 whichsig_pv (const char *sig)I32 whichsig_pvn(const char *sig, STRLEN len)I32 whichsig_sv (SV *sigsv)These variables give details as to where various libraries, installation destinations,etc., go, as well as what various installation options were selected
ARCHLIBThis variable, if defined, holds the name of the directory in which the user wants to put architecture-dependent public library files for perl5. It is most often a local directory such as/usr/local/lib. Programs using this variable must be prepared to deal with filename expansion. IfARCHLIB is the same asPRIVLIB, it is not defined, since presumably the program already searchesPRIVLIB.
ARCHLIB_EXPThis symbol contains the ~name expanded version ofARCHLIB, to be used in programs that are not prepared to deal with ~ expansion at run-time.
ARCHNAMEThis symbol holds a string representing the architecture name. It may be used to construct an architecture-dependant pathname where library files may be held under a private library, for instance.
BINThis symbol holds the path of the bin directory where the package will be installed. Program must be prepared to deal with ~name substitution.
BIN_EXPThis symbol is the filename expanded version of theBIN symbol, for programs that do not want to deal with that at run-time.
INSTALL_USR_BIN_PERLThis symbol, if defined, indicates that Perl is to be installed also as/usr/bin/perl.
MULTIARCHThis symbol, if defined, signifies that the build process will produce some binary files that are going to be used in a cross-platform environment. This is the case for example with the NeXT "fat" binaries that contain executables for severalCPUs.
PERL_INC_VERSION_LISTThis variable specifies the list of subdirectories in over whichperl.c:incpush() andlib/lib.pm will automatically search when adding directories to @INC, in a format suitable for a C initialization string. See theinc_version_list entry in Porting/Glossary for more details.
PERL_OTHERLIBDIRSThis variable contains a colon-separated set of paths for the perl binary to search for additional library files or modules. These directories will be tacked to the end of @INC. Perl will automatically search below each path for version- and architecture-specific directories. See"PERL_INC_VERSION_LIST" for more details.
PERL_RELOCATABLE_INCThis symbol, if defined, indicates that we'd like to relocate entries in @INC at run time based on the location of the perl binary.
PERL_TARGETARCHThis symbol, if defined, indicates the target architecture Perl has been cross-compiled to. Undefined if not a cross-compile.
PERL_USE_DEVELThis symbol, if defined, indicates that Perl was configured with-Dusedevel, to enable development features. This should not be done for production builds.
PERL_VENDORARCHIf defined, this symbol contains the name of a private library. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own architecture-dependent modules and extensions in this directory with
MakeMaker Makefile.PL INSTALLDIRS=vendoror equivalent. SeeINSTALL for details.
PERL_VENDORARCH_EXPThis symbol contains the ~name expanded version ofPERL_VENDORARCH, to be used in programs that are not prepared to deal with ~ expansion at run-time.
PERL_VENDORLIB_EXPThis symbol contains the ~name expanded version ofVENDORLIB, to be used in programs that are not prepared to deal with ~ expansion at run-time.
PERL_VENDORLIB_STEMThis define isPERL_VENDORLIB_EXP with any trailing version-specific component removed. The elements ininc_version_list (inc_version_list.U (part of metaconfig)) can be tacked onto this variable to generate a list of directories to search.
PRIVLIBThis symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion.
PRIVLIB_EXPThis symbol contains the ~name expanded version ofPRIVLIB, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITEARCHThis symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-dependent modules in this directory with
MakeMaker Makefile.PLor equivalent. SeeINSTALL for details.
SITEARCH_EXPThis symbol contains the ~name expanded version ofSITEARCH, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITELIBThis symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-independent modules in this directory with
MakeMaker Makefile.PLor equivalent. SeeINSTALL for details.
SITELIB_EXPThis symbol contains the ~name expanded version ofSITELIB, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITELIB_STEMThis define isSITELIB_EXP with any trailing version-specific component removed. The elements ininc_version_list (inc_version_list.U (part of metaconfig)) can be tacked onto this variable to generate a list of directories to search.
STARTPERLThis variable contains the string to put in front of a perl script to make sure (one hopes) that it runs with perl and not some shell.
USE_64_BIT_ALLThis symbol, if defined, indicates that 64-bit integers should be used when available. If not defined, the native integers will be used (be they 32 or 64 bits). The maximal possible 64-bitness is employed: LP64 orILP64, meaning that you will be able to use more than 2 gigabytes of memory. This mode is even more binary incompatible thanUSE_64_BIT_INT. You may not be able to run the resulting executable in a 32-bitCPU at all or you may need at least to reboot your OS to 64-bit mode.
USE_64_BIT_INTThis symbol, if defined, indicates that 64-bit integers should be used when available. If not defined, the native integers will be employed (be they 32 or 64 bits). The minimal possible 64-bitness is used, just enough to get 64-bit integers into Perl. This may mean using for example "long longs", while your memory may still be limited to 2 gigabytes.
USE_BSD_GETPGRPThis symbol, if defined, indicates that getpgrp needs one arguments whereasUSG one needs none.
USE_BSD_SETPGRPThis symbol, if defined, indicates that setpgrp needs two arguments whereasUSG one needs none. See also"HAS_SETPGID" for aPOSIX interface.
USE_C_BACKTRACEThis symbol, if defined, indicates that Perl should be built with support for backtrace.
USE_CPLUSPLUSThis symbol, if defined, indicates that a C++ compiler was used to compiled Perl and will be used to compile extensions.
USE_CROSS_COMPILEThis symbol, if defined, indicates that Perl is being cross-compiled.
USE_DTRACEThis symbol, if defined, indicates that Perl should be built with support for DTrace.
USE_DYNAMIC_LOADINGThis symbol, if defined, indicates that dynamic loading of some sort is available.
USE_FAST_STDIOThis symbol, if defined, indicates that Perl should be built to use 'fast stdio'. Defaults to define in Perls 5.8 and earlier, to undef later.
USE_ITHREADSThis symbol, if defined, indicates that Perl should be built to use the interpreter-based threading implementation.
USE_KERN_PROC_PATHNAMEThis symbol, if defined, indicates that we can use sysctl withKERN_PROC_PATHNAME to get a full path for the executable, and hence convert $^X to an absolute path.
USE_LARGE_FILESThis symbol, if defined, indicates that large file support should be used when available.
USE_LONG_DOUBLEThis symbol, if defined, indicates that long doubles should be used when available.
USE_MORE_BITSThis symbol, if defined, indicates that 64-bit interfaces and long doubles should be used when available.
USE_NSGETEXECUTABLEPATHThis symbol, if defined, indicates that we can use_NSGetExecutablePath and realpath to get a full path for the executable, and hence convert $^X to an absolute path.
USE_PERLIOThis symbol, if defined, indicates that the PerlIO abstraction should be used throughout. If not defined, stdio should be used in a fully backward compatible manner.
USE_QUADMATHThis symbol, if defined, indicates that the quadmath library should be used when available.
USE_REENTRANT_APIThis symbol, if defined, indicates that Perl should try to use the various_r versions of library functions. This is extremely experimental.
USE_SEMCTL_SEMID_DSThis symbol, if defined, indicates thatstruct semid_ds * is used for semctlIPC_STAT.
USE_SEMCTL_SEMUNThis symbol, if defined, indicates thatunion semun is used for semctlIPC_STAT.
USE_SITECUSTOMIZEThis symbol, if defined, indicates that sitecustomize should be used.
USE_SOCKSThis symbol, if defined, indicates that Perl should be built to use socks.
USE_STAT_BLOCKSThis symbol is defined if this system has a stat structure declaringst_blksize andst_blocks.
USE_STDIO_BASEThis symbol is defined if the_base field (or similar) of the stdioFILE structure can be used to access the stdio buffer for a file handle. If this is defined, then theFILE_base(fp) macro will also be defined and should be used to access this field. Also, theFILE_bufsiz(fp) macro will be defined and should be used to determine the number of bytes in the buffer.USE_STDIO_BASE will never be defined unlessUSE_STDIO_PTR is.
USE_STDIO_PTRThis symbol is defined if the_ptr and_cnt fields (or similar) of the stdioFILE structure can be used to access the stdio buffer for a file handle. If this is defined, then theFILE_ptr(fp) andFILE_cnt(fp) macros will also be defined and should be used to access these fields.
USE_STRICT_BY_DEFAULTThis symbol, if defined, enables additional defaults. At this time it only enables implicit strict by default.
USE_THREADSThis symbol, if defined, indicates that Perl should be built to use threads. At present, it is a synonym for andUSE_ITHREADS, but eventually the source ought to be changed to use this to mean_any_ threading implementation.
HAS_SOCKADDR_IN6This symbol, if defined, indicates the availability ofstruct sockaddr_in6;
HAS_SOCKADDR_SA_LENThis symbol, if defined, indicates that thestruct sockaddr structure has a member calledsa_len, indicating the length of the structure.
HAS_SOCKADDR_STORAGEThis symbol, if defined, indicates the availability ofstruct sockaddr_storage;
HAS_SOCKATMARKThis symbol, if defined, indicates that thesockatmark routine is available to test whether a socket is at the out-of-band mark.
HAS_SOCKETThis symbol, if defined, indicates that theBSDsocket interface is supported.
HAS_SOCKETPAIRThis symbol, if defined, indicates that theBSDsocketpair() call is supported.
HAS_SOCKS5_INITThis symbol, if defined, indicates that thesocks5_init routine is available to initializeSOCKS 5.
I_SOCKSThis symbol, if defined, indicates thatsocks.h exists and should be included.
#ifdef I_SOCKS #include <socks.h>#endifI_SYS_SOCKIOThis symbol, if defined, indicates thesys/sockio.h should be included to get socket ioctl options, likeSIOCATMARK.
#ifdef I_SYS_SOCKIO #include <sys_sockio.h>#endifapply_builtin_cv_attributesGiven an OP_LIST containing attribute definitions, filter it for known builtin attributes to apply to the cv, returning a possibly-smaller list containing just the remaining ones.
OP * apply_builtin_cv_attributes(CV *cv, OP *attrlist)filter_addDescribed inperlfilter.
SV * filter_add(filter_t funcp, SV *datasv)filter_delDelete most recently added instance of the filter function argument
void filter_del(filter_t funcp)filter_readDescribed inperlfilter.
I32 filter_read(int idx, SV *buf_sv, int maxlen)scan_vstringReturns a pointer to the next character after the parsed vstring, as well as updating the passed in sv.
Function must be called like
sv = sv_2mortal(newSV(5));s = scan_vstring(s,e,sv);where s and e are the start and end of the string. The sv should already be large enough to store the vstring passed in, for performance reasons.
This function may croak if fatal warnings are enabled in the calling scope, hence the sv_2mortal in the example (to prevent a leak). Make sure to do SvREFCNT_inc afterwards if you use sv_2mortal.
char * scan_vstring(const char *s, const char * const e, SV *sv)start_subparseSet things up for parsing a subroutine.
Ifis_format is non-zero, the input is to be considered a format sub (a specialised sub used to implement perl'sformat feature); else a normalsub.
flags are added to the flags forPL_compcv.flags may include theCVf_IsMETHOD bit, which causes the new subroutine to be a method.
This returns the value ofPL_savestack_ix that was in effect upon entry to the function;
I32 start_subparse(I32 is_format, U32 flags)dMARKDeclare a stack marker variable,mark, for the XSUB. See"MARK" and"dORIGMARK".
dMARK;dORIGMARKSaves the original stack mark for the XSUB. See"ORIGMARK".
dORIGMARK;dSPDeclares a local copy of perl's stack pointer for the XSUB, available via theSP macro. See"SP".
dSP;dTARGETDeclare that this function usesTARG, and initializes it
dTARGET;EXTENDUsed to extend the argument stack for an XSUB's return values. Once used, guarantees that there is room for at leastnitems to be pushed onto the stack.
void EXTEND(SP, SSize_t nitems)mPUSHiPush an integer onto the stack. The stack must have room for this element. Does not useTARG. See also"PUSHi","mXPUSHi" and"XPUSHi".
void mPUSHi(IV iv)mPUSHnPush a double onto the stack. The stack must have room for this element. Does not useTARG. See also"PUSHn","mXPUSHn" and"XPUSHn".
void mPUSHn(NV nv)mPUSHpPush a string onto the stack. The stack must have room for this element. Thelen indicates the length of the string. Does not useTARG. See also"PUSHp","mXPUSHp" and"XPUSHp".
void mPUSHp(char* str, STRLEN len)mPUSHpvsA variation onmPUSHp that takes a literal string and calculates its size directly.
void mPUSHpvs("literal string")mPUSHsPush an SV onto the stack and mortalizes the SV. The stack must have room for this element. Does not useTARG. See also"PUSHs" and"mXPUSHs".
void mPUSHs(SV* sv)mPUSHuPush an unsigned integer onto the stack. The stack must have room for this element. Does not useTARG. See also"PUSHu","mXPUSHu" and"XPUSHu".
void mPUSHu(UV uv)mXPUSHiPush an integer onto the stack, extending the stack if necessary. Does not useTARG. See also"XPUSHi","mPUSHi" and"PUSHi".
void mXPUSHi(IV iv)mXPUSHnPush a double onto the stack, extending the stack if necessary. Does not useTARG. See also"XPUSHn","mPUSHn" and"PUSHn".
void mXPUSHn(NV nv)mXPUSHpPush a string onto the stack, extending the stack if necessary. Thelen indicates the length of the string. Does not useTARG. See also"XPUSHp",mPUSHp andPUSHp.
void mXPUSHp(char* str, STRLEN len)mXPUSHpvsA variation onmXPUSHp that takes a literal string and calculates its size directly.
void mXPUSHpvs("literal string")mXPUSHsPush an SV onto the stack, extending the stack if necessary and mortalizes the SV. Does not useTARG. See also"XPUSHs" and"mPUSHs".
void mXPUSHs(SV* sv)mXPUSHuPush an unsigned integer onto the stack, extending the stack if necessary. Does not useTARG. See also"XPUSHu","mPUSHu" and"PUSHu".
void mXPUSHu(UV uv)newXSprotoUsed byxsubpp to hook up XSUBs as Perl subs. Adds Perl prototypes to the subs.
ORIGMARKThe original stack mark for the XSUB. See"dORIGMARK".
POPiPops an integer off the stack.
IV POPiPOPlPops a long off the stack.
long POPlPOPnPops a double off the stack.
NV POPnPOPpPops a string off the stack.
char* POPpPOPpbytexPops a string off the stack which must consist of bytes i.e. characters < 256.
char* POPpbytexPOPpxPops a string off the stack. Identical to POPp. There are two names for historical reasons.
char* POPpxPOPsPops an SV off the stack.
SV* POPsPOPuPops an unsigned integer off the stack.
UV POPuPOPulPops an unsigned long off the stack.
long POPulPUSHiPush an integer onto the stack. The stack must have room for this element. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mPUSHi" instead. See also"XPUSHi" and"mXPUSHi".
void PUSHi(IV iv)PUSHmortalPush a new mortal SV onto the stack. The stack must have room for this element. Does not useTARG. See also"PUSHs","XPUSHmortal" and"XPUSHs".
void PUSHmortalPUSHnPush a double onto the stack. The stack must have room for this element. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mPUSHn" instead. See also"XPUSHn" and"mXPUSHn".
void PUSHn(NV nv)PUSHpPush a string onto the stack. The stack must have room for this element. Thelen indicates the length of the string. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mPUSHp" instead. See also"XPUSHp" and"mXPUSHp".
void PUSHp(char* str, STRLEN len)PUSHpvsA variation onPUSHp that takes a literal string and calculates its size directly.
void PUSHpvs("literal string")PUSHsPush an SV onto the stack. The stack must have room for this element. Does not handle 'set' magic. Does not useTARG. See also"PUSHmortal","XPUSHs", and"XPUSHmortal".
void PUSHs(SV* sv)PUSHuPush an unsigned integer onto the stack. The stack must have room for this element. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mPUSHu" instead. See also"XPUSHu" and"mXPUSHu".
void PUSHu(UV uv)PUTBACKClosing bracket for XSUB arguments. This is usually handled byxsubpp. See"PUSHMARK" andperlcall for other uses.
PUTBACK;SSNEWSSNEWaSSNEWatSSNEWtThese each temporarily allocate data on the savestack, returning an SSize_t index into the savestack, because a pointer would get broken if the savestack is moved on reallocation. Use"SSPTR" to convert the returned index into a pointer.
The forms differ in that plainSSNEW allocatessize bytes;SSNEWt andSSNEWat allocatesize objects, each of which is typetype; and <SSNEWa> andSSNEWat make sure to align the new data to analign boundary. The most useful value for the alignment is likely to be"MEM_ALIGNBYTES". The alignment will be preserved through savestack reallocationonly if realloc returns data aligned to a size divisible by "align"!
SSize_t SSNEW (Size_t size)SSize_t SSNEWa (Size_t size, Size_t align)SSize_t SSNEWat(Size_t size, type, Size_t align)SSize_t SSNEWt (Size_t size, type)SSPTRSSPTRtThese convert theindex returned by L/<SSNEW> and kin into actual pointers.
The difference is thatSSPTR casts the result totype, andSSPTRt casts it to a pointer of thattype.
type SSPTR (SSize_t index, type)type * SSPTRt(SSize_t index, type)TARGTARG is short for "target". It is an entry in the pad that an OPsop_targ refers to. It is scratchpad space, often used as a return value for the OP, but some use it for other purposes.
TARG;XPUSHiPush an integer onto the stack, extending the stack if necessary. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mXPUSHi" instead. See also"PUSHi" and"mPUSHi".
void XPUSHi(IV iv)XPUSHmortalPush a new mortal SV onto the stack, extending the stack if necessary. Does not useTARG. See also"XPUSHs","PUSHmortal" and"PUSHs".
void XPUSHmortalXPUSHnPush a double onto the stack, extending the stack if necessary. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mXPUSHn" instead. See also"PUSHn" and"mPUSHn".
void XPUSHn(NV nv)XPUSHpPush a string onto the stack, extending the stack if necessary. Thelen indicates the length of the string. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mXPUSHp" instead. See also"PUSHp" and"mPUSHp".
void XPUSHp(char* str, STRLEN len)XPUSHpvsA variation onXPUSHp that takes a literal string and calculates its size directly.
void XPUSHpvs("literal string")XPUSHsPush an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. Does not useTARG. See also"XPUSHmortal",PUSHs andPUSHmortal.
void XPUSHs(SV* sv)XPUSHuPush an unsigned integer onto the stack, extending the stack if necessary. Handles 'set' magic. UsesTARG, sodTARGET ordXSTARG should be called to declare it. Do not call multipleTARG-oriented macros to return lists from XSUB's - see"mXPUSHu" instead. See also"PUSHu" and"mPUSHu".
void XPUSHu(UV uv)XS_APIVERSION_BOOTCHECKMacro to verify that the perl api version an XS module has been compiled against matches the api version of the perl interpreter it's being loaded into.
XS_APIVERSION_BOOTCHECK;XSRETURNReturn from XSUB, indicating number of items on the stack. This is usually handled byxsubpp.
void XSRETURN(int nitems)XSRETURN_EMPTYReturn an empty list from an XSUB immediately.
XSRETURN_EMPTY;XSRETURN_IVReturn an integer from an XSUB immediately. UsesXST_mIV.
void XSRETURN_IV(IV iv)XSRETURN_NOReturn&PL_sv_no from an XSUB immediately. UsesXST_mNO.
XSRETURN_NO;XSRETURN_NVReturn a double from an XSUB immediately. UsesXST_mNV.
void XSRETURN_NV(NV nv)XSRETURN_PVReturn a copy of a string from an XSUB immediately. UsesXST_mPV.
void XSRETURN_PV(char* str)XSRETURN_UNDEFReturn&PL_sv_undef from an XSUB immediately. UsesXST_mUNDEF.
XSRETURN_UNDEF;XSRETURN_UVReturn an integer from an XSUB immediately. UsesXST_mUV.
void XSRETURN_UV(IV uv)XSRETURN_YESReturn&PL_sv_yes from an XSUB immediately. UsesXST_mYES.
XSRETURN_YES;XST_mIVPlace an integer into the specified positionpos on the stack. The value is stored in a new mortal SV.
void XST_mIV(int pos, IV iv)XST_mNOPlace&PL_sv_no into the specified positionpos on the stack.
void XST_mNO(int pos)XST_mNVPlace a double into the specified positionpos on the stack. The value is stored in a new mortal SV.
void XST_mNV(int pos, NV nv)XST_mPVPlace a copy of a string into the specified positionpos on the stack. The value is stored in a new mortal SV.
void XST_mPV(int pos, char* str)XST_mUNDEFPlace&PL_sv_undef into the specified positionpos on the stack.
void XST_mUNDEF(int pos)XST_mUVPlace an unsigned integer into the specified positionpos on the stack. The value is stored in a new mortal SV.
void XST_mUV(int pos, UV uv)XST_mYESPlace&PL_sv_yes into the specified positionpos on the stack.
void XST_mYES(int pos)XS_VERSIONThe version identifier for an XS module. This is usually handled automatically byExtUtils::MakeMaker. See"XS_VERSION_BOOTCHECK".
XS_VERSION_BOOTCHECKMacro to verify that a PM module's$VERSION variable matches the XS module'sXS_VERSION variable. This is usually handled automatically byxsubpp. See"The VERSIONCHECK: Keyword" in perlxs.
XS_VERSION_BOOTCHECK;See also"Unicode Support".
CAT2This macro concatenates 2 tokens together.
token CAT2(token x, token y)CopyCopyDThe XSUB-writer's interface to the Cmemcpy function. Thesrc is the source,dest is the destination,nitems is the number of items, andtype is the type. May fail on overlapping copies. See also"Move".
CopyD is likeCopy but returnsdest. Useful for encouraging compilers to tail-call optimise.
void Copy (void* src, void* dest, int nitems, type)void * CopyD(void* src, void* dest, int nitems, type)delimcpyCopy a source buffer to a destination buffer, stopping at (but not including) the first occurrence in the source of an unescaped (defined below) delimiter byte,delim. The source is the bytes betweenfrom andfrom_end - 1. Similarly, the dest isto up toto_end.
The number of bytes copied is written to*retlen.
Returns the position of the first uncopieddelim in thefrom buffer, but if there is no such occurrence beforefrom_end, thenfrom_end is returned, and the entire bufferfrom ..from_end - 1 is copied.
If there is room in the destination available after the copy, an extra terminating safetyNUL byte is appended (not included in the returned length).
The error case is if the destination buffer is not large enough to accommodate everything that should be copied. In this situation, a value larger thanto_end -to is written to*retlen, and as much of the source as fits will be written to the destination. Not having room for the safetyNUL is not considered an error.
In the following examples, letx be the delimiter, and0 represent aNUL byte (NOT the digit0). Then we would have
Source Destinationabcxdef abc0provided the destination buffer is at least 4 bytes long.
An escaped delimiter is one which is immediately preceded by a single backslash. Escaped delimiters are copied, and the copy continues past the delimiter; the backslash is not copied:
Source Destinationabc\xdef abcxdef0(provided the destination buffer is at least 8 bytes long).
It's actually somewhat more complicated than that. A sequence of any odd number of backslashes escapes the following delimiter, and the copy continues with exactly one of the backslashes stripped.
Source Destination abc\xdef abcxdef0 abc\\\xdef abc\\xdef0abc\\\\\xdef abc\\\\xdef0(as always, if the destination is large enough)
An even number of preceding backslashes does not escape the delimiter, so that the copy stops just before it, and includes all the backslashes (no stripping; zero is considered even):
Source Destination abcxdef abc0 abc\\xdef abc\\0abc\\\\xdef abc\\\\0char * delimcpy(char *to, const char *to_end, const char *from, const char *from_end, const int delim, I32 *retlen)do_joinThis performs a Perljoin, placing the joined output intosv.
The elements to join are in SVs, stored in a C array of pointers to SVs, from**mark to**sp - 1. Hence*mark is a reference to the first SV. Each SV will be coerced into a PV if not one already.
delim contains the string (or coerced into a string) that is to separate each of the joined elements.
If any component is in UTF-8, the result will be as well, and all non-UTF-8 components will be converted to UTF-8 as necessary.
Magic and tainting are handled.
void do_join(SV *sv, SV *delim, SV **mark, SV **sp)do_sprintfThis performs a Perlsprintf placing the string output intosv.
The elements to format are in SVs, stored in a C array of pointers to SVs of lengthlen> and beginning at**sarg. The element referenced by*sarg is the format.
Magic and tainting are handled.
void do_sprintf(SV *sv, SSize_t len, SV **sarg)fbm_compileAnalyzes the string in order to make fast searches on it usingfbm_instr() -- the Boyer-Moore algorithm.
void fbm_compile(SV *sv, U32 flags)fbm_instrReturns the location of the SV in the string delimited bybig andbigend (bigend) is the char following the last char). It returnsNULL if the string can't be found. Thesv does not have to befbm_compiled, but the search will not be as fast then.
char * fbm_instr(unsigned char *big, unsigned char *bigend, SV *littlestr, U32 flags)foldEQReturns true if the leadinglen bytes of the stringss1 ands2 are the same case-insensitively; false otherwise. Uppercase and lowercase ASCII range bytes match themselves and their opposite case counterparts. Non-cased and non-ASCII range bytes match only themselves.
I32 foldEQ(const char *a, const char *b, I32 len)ibcmpThis is a synonym for(! foldEQ())
I32 ibcmp(const char *a, const char *b, I32 len)ibcmp_localeThis is a synonym for(! foldEQ_locale())
I32 ibcmp_locale(const char *a, const char *b, I32 len)ibcmp_utf8This is a synonym for(! foldEQ_utf8())
I32 ibcmp_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)instrSame asstrstr(3), which finds and returns a pointer to the first occurrence of the NUL-terminated substringlittle in the NUL-terminated stringbig, returning NULL if not found. The terminating NUL bytes are not compared.
char * instr(const char *big, const char *little)memCHRsReturns the position of the first occurrence of the bytec in the literal string"list", or NULL ifc doesn't appear in"list". All bytes are treated as unsigned char. Thus this macro can be used to determine ifc is in a set of particular characters. Unlikestrchr(3), it works even ifc isNUL (and the set doesn't includeNUL).
bool memCHRs("list", char c)memEQTest two buffers (which may contain embeddedNUL characters, to see if they are equal. Thelen parameter indicates the number of bytes to compare. Returns true or false. It is undefined behavior if either of the buffers doesn't contain at leastlen bytes.
bool memEQ(char* s1, char* s2, STRLEN len)memEQsLike"memEQ", but the second string is a literal enclosed in double quotes,l1 gives the number of bytes ins1. Returns true or false.
bool memEQs(char* s1, STRLEN l1, "s2")memNETest two buffers (which may contain embeddedNUL characters, to see if they are not equal. Thelen parameter indicates the number of bytes to compare. Returns true or false. It is undefined behavior if either of the buffers doesn't contain at leastlen bytes.
bool memNE(char* s1, char* s2, STRLEN len)memNEsLike"memNE", but the second string is a literal enclosed in double quotes,l1 gives the number of bytes ins1. Returns true or false.
bool memNEs(char* s1, STRLEN l1, "s2")MoveMoveDThe XSUB-writer's interface to the Cmemmove function. Thesrc is the source,dest is the destination,nitems is the number of items, andtype is the type. Can do overlapping moves. See also"Copy".
MoveD is likeMove but returnsdest. Useful for encouraging compilers to tail-call optimise.
void Move (void* src, void* dest, int nitems, type)void * MoveD(void* src, void* dest, int nitems, type)my_snprintfThe C librarysnprintf functionality, if available and standards-compliant (usesvsnprintf, actually). However, if thevsnprintf is not available, will unfortunately use the unsafevsprintf which can overrun the buffer (there is an overrun check, but that may be too late). Consider usingsv_vcatpvf instead, or gettingvsnprintf.
int my_snprintf(char *buffer, const Size_t len, const char *format, ...)my_sprintfDEPRECATED! It is planned to removemy_sprintf from a future release of Perl. Do not use it for new code; remove it from existing code.
Do NOT use this due to the possibility of overflowingbuffer. Instead use my_snprintf()
int my_sprintf(NN char *buffer, NN const char *pat, ...)my_strnlenThe C librarystrnlen if available, or a Perl implementation of it.
my_strnlen() computes the length of the string, up tomaxlen bytes. It will never attempt to address more thanmaxlen bytes, making it suitable for use with strings that are not guaranteed to be NUL-terminated.
Size_t my_strnlen(const char *str, Size_t maxlen)my_vsnprintfThe C libraryvsnprintf if available and standards-compliant. However, if thevsnprintf is not available, will unfortunately use the unsafevsprintf which can overrun the buffer (there is an overrun check, but that may be too late). Consider usingsv_vcatpvf instead, or gettingvsnprintf.
int my_vsnprintf(char *buffer, const Size_t len, const char *format, va_list ap)NewCopyCombines Newx() and Copy() into a single macro. Dest will be allocated using Newx() and then src will be copied into it.
void NewCopy(void* src, void* dest, int nitems, type)ninstrFind the first (leftmost) occurrence of a sequence of bytes within another sequence. This is the Perl version ofstrstr(), extended to handle arbitrary sequences, potentially containing embeddedNUL characters (NUL is what the initialn in the function name stands for; some systems have an equivalent,memmem(), but with a somewhat different API).
Another way of thinking about this function is finding a needle in a haystack.big points to the first byte in the haystack.big_end points to one byte beyond the final byte in the haystack.little points to the first byte in the needle.little_end points to one byte beyond the final byte in the needle. All the parameters must be non-NULL.
The function returnsNULL if there is no occurrence oflittle withinbig. Iflittle is the empty string,big is returned.
Because this function operates at the byte level, and because of the inherent characteristics of UTF-8 (or UTF-EBCDIC), it will work properly if both the needle and the haystack are strings with the same UTF-8ness, but not if the UTF-8ness differs.
char * ninstr(const char *big, const char *bigend, const char *little, const char *lend)NullchNull character pointer. (No longer available whenPERL_CORE is defined.)
PL_naA scratch pad variable in which to store aSTRLEN value. If would have been better named something likePL_temp_strlen.
It is is typically used withSvPV when one is actually planning to discard the returned length, (hence the length is "Not Applicable", which is how this variable got its name).
BUT BEWARE, if this is used in a situation where something that is using it is in a call stack with something else that is using it, this variable would get zapped, leading to hard-to-diagnose errors.
It is usually more efficient to either declare a local variable and use that instead, or to use theSvPV_nolen macro.
STRLEN PL_narninstrLike"ninstr", but instead finds the final (rightmost) occurrence of a sequence of bytes within another sequence, returningNULL if there is no such occurrence.
char * rninstr(const char *big, const char *bigend, const char *little, const char *lend)savepvPerl's version ofstrdup(). Returns a pointer to a newly allocated string which is a duplicate ofpv. The size of the string is determined bystrlen(), which means it may not contain embeddedNUL characters and must have a trailingNUL. To prevent memory leaks, the memory allocated for the new string needs to be freed when no longer needed. This can be done with the"Safefree" function, orSAVEFREEPV.
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as"savesharedpv".
char * savepv(const char *pv)savepvnPerl's version of whatstrndup() would be if it existed. Returns a pointer to a newly allocated string which is a duplicate of the firstlen bytes frompv, plus a trailingNUL byte. The memory allocated for the new string can be freed with theSafefree() function.
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as"savesharedpvn".
char * savepvn(const char *pv, Size_t len)savepvsLikesavepvn, but takes a literal string instead of a string/length pair.
char* savepvs("literal string")savesharedpvA version ofsavepv() which allocates the duplicate string in memory which is shared between threads.
char * savesharedpv(const char *pv)savesharedpvnA version ofsavepvn() which allocates the duplicate string in memory which is shared between threads. (With the specific difference that aNULL pointer is not acceptable)
char * savesharedpvn(const char * const pv, const STRLEN len)savesharedpvsA version ofsavepvs() which allocates the duplicate string in memory which is shared between threads.
char* savesharedpvs("literal string")savesharedsvpvA version ofsavesharedpv() which allocates the duplicate string in memory which is shared between threads.
char * savesharedsvpv(SV *sv)savesvpvA version ofsavepv()/savepvn() which gets the string to duplicate from the passed in SV usingSvPV()
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as"savesharedsvpv".
char * savesvpv(SV *sv)strEQTest twoNUL-terminated strings to see if they are equal. Returns true or false.
bool strEQ(char* s1, char* s2)strGETest twoNUL-terminated strings to see if the first,s1, is greater than or equal to the second,s2. Returns true or false.
bool strGE(char* s1, char* s2)strGTTest twoNUL-terminated strings to see if the first,s1, is greater than the second,s2. Returns true or false.
bool strGT(char* s1, char* s2)STRINGIFYThis macro surrounds its token with double quotes.
string STRINGIFY(token x)strLETest twoNUL-terminated strings to see if the first,s1, is less than or equal to the second,s2. Returns true or false.
bool strLE(char* s1, char* s2)strLTTest twoNUL-terminated strings to see if the first,s1, is less than the second,s2. Returns true or false.
bool strLT(char* s1, char* s2)strNETest twoNUL-terminated strings to see if they are different. Returns true or false.
bool strNE(char* s1, char* s2)strnEQTest twoNUL-terminated strings to see if they are equal. Thelen parameter indicates the number of bytes to compare. Returns true or false. (A wrapper forstrncmp).
bool strnEQ(char* s1, char* s2, STRLEN len)strnNETest twoNUL-terminated strings to see if they are different. Thelen parameter indicates the number of bytes to compare. Returns true or false. (A wrapper forstrncmp).
bool strnNE(char* s1, char* s2, STRLEN len)STR_WITH_LENReturns two comma separated tokens of the input literal string, and its length. This is convenience macro which helps out in some API calls. Note that it can't be used as an argument to macros or functions that under some configurations might be macros, which means that it requires the full Perl_xxx(aTHX_ ...) form for any API calls where it's used.
pair STR_WITH_LEN("literal string")ZeroZeroDThe XSUB-writer's interface to the Cmemzero function. Thedest is the destination,nitems is the number of items, andtype is the type.
ZeroD is likeZero but returnsdest. Useful for encouraging compilers to tail-call optimise.
void Zero (void* dest, int nitems, type)void * ZeroD(void* dest, int nitems, type)SVt_PVOBJNOTE:SVt_PVOBJ isexperimental and may change or be removed without notice.
Type flag for object instances. See"svtype".
svtypeAn enum of flags for Perl types. These are found in the filesv.h in thesvtype enum. Test these flags with theSvTYPE macro.
The types are:
SVt_NULLSVt_IVSVt_NVSVt_RVSVt_PVSVt_PVIVSVt_PVNVSVt_PVMGSVt_INVLISTSVt_REGEXPSVt_PVGVSVt_PVLVSVt_PVAVSVt_PVHVSVt_PVCVSVt_PVFMSVt_PVIOSVt_PVOBJThese are most easily explained from the bottom up.
SVt_PVOBJ is for object instances of the new `use feature 'class'` kind.SVt_PVIO is for I/O objects,SVt_PVFM for formats,SVt_PVCV for subroutines,SVt_PVHV for hashes andSVt_PVAV for arrays.
All the others are scalar types, that is, things that can be bound to a$ variable. For these, the internal types are mostly orthogonal to types in the Perl language.
Hence, checkingSvTYPE(sv) < SVt_PVAV is the best way to see whether something is a scalar.
SVt_PVGV represents a typeglob. If!SvFAKE(sv), then it is a real, incoercible typeglob. IfSvFAKE(sv), then it is a scalar to which a typeglob has been assigned. Assigning to it again will stop it from being a typeglob.SVt_PVLV represents a scalar that delegates to another scalar behind the scenes. It is used, e.g., for the return value ofsubstr and for tied hash and array elements. It can hold any scalar value, including a typeglob.SVt_REGEXP is for regular expressions.SVt_INVLIST is for Perl core internal use only.
SVt_PVMG represents a "normal" scalar (not a typeglob, regular expression, or delegate). Since most scalars do not need all the internal fields of a PVMG, we save memory by allocating smaller structs when possible. All the other types are just simpler forms ofSVt_PVMG, with fewer internal fields.SVt_NULL can only hold undef.SVt_IV can hold undef, an integer, or a reference. (SVt_RV is an alias forSVt_IV, which exists for backward compatibility.)SVt_NV can hold undef or a double. (In builds that support headless NVs, these could also hold a reference via a suitable offset, in the same way that SVt_IV does, but this is not currently supported and seems to be a rare use case.)SVt_PV can holdundef, a string, or a reference.SVt_PVIV is a superset ofSVt_PV andSVt_IV.SVt_PVNV is a superset ofSVt_PV andSVt_NV.SVt_PVMG can hold anythingSVt_PVNV can hold, but it may also be blessed or magical.
AV_FROM_REFCV_FROM_REFHV_FROM_REFThe*V_FROM_REF macros extract theSvRV() from a given reference SV and return a suitably-cast to pointer to the referenced SV. When running under-DDEBUGGING, assertions are also applied that check thatref is definitely a reference SV that refers to an SV of the right type.
AV * AV_FROM_REF(SV * ref)CV * CV_FROM_REF(SV * ref)HV * HV_FROM_REF(SV * ref)BOOL_INTERNALS_sv_isboolChecks if aSvBoolFlagsOK() sv is a bool.Note that it is the caller's responsibility to ensure that the sv isSvBoolFlagsOK() before calling this. This is only useful in specialized logic like serialization code where performance is critical and the flags have already been checked to be correct. Almost always you should be usingsv_isbool(sv) instead.
bool BOOL_INTERNALS_sv_isbool(SV* sv)BOOL_INTERNALS_sv_isbool_falseChecks if aSvBoolFlagsOK() sv is a false bool.Note that it is the caller's responsibility to ensure that the sv isSvBoolFlagsOK() before calling this. This is only useful in specialized logic like serialization code where performance is critical and the flags have already been checked to be correct. This isNOT what you should use to check if an SV is "false", for that you should be using!SvTRUE(sv) instead.
bool BOOL_INTERNALS_sv_isbool_false(SV* sv)BOOL_INTERNALS_sv_isbool_trueChecks if aSvBoolFlagsOK() sv is a true bool.Note that it is the caller's responsibility to ensure that the sv isSvBoolFlagsOK() before calling this. This is only useful in specialized logic like serialization code where performance is critical and the flags have already been checked to be correct. This isNOT what you should use to check if an SV is "true", for that you should be usingSvTRUE(sv) instead.
bool BOOL_INTERNALS_sv_isbool_true(SV* sv)boolSVReturns a true SV ifb is a true value, or a false SV ifb is 0.
See also"PL_sv_yes" and"PL_sv_no".
SV * boolSV(bool b)croak_xs_usageA specialised variant ofcroak() for emitting the usage message for xsubs
croak_xs_usage(cv, "eee_yow");works out the package name and subroutine name fromcv, and then callscroak(). Hence ifcv is&ouch::awk, it would callcroak as:
diag_listed_as: SKIPMEPerl_croak(aTHX_ "Usage: %" SVf "::%" SVf "(%s)", "ouch" "awk", "eee_yow");void croak_xs_usage(const CV * const cv, const char * const params)DEFSVReturns the SV associated with$_
SV * DEFSVDEFSV_setAssociatesv with$_
void DEFSV_set(SV * sv)get_svReturns the SV of the specified Perl scalar.flags are passed to"gv_fetchpv". IfGV_ADD is set and the Perl variable does not exist then it will be created. Ifflags is zero and the variable does not exist then NULL is returned.
NOTE: theperl_get_sv() form isdeprecated.
SV * get_sv(const char *name, I32 flags)isGV_with_GPReturns a boolean as to whether or notsv is a GV with a pointer to a GP (glob pointer).
bool isGV_with_GP(SV * sv)looks_like_numberTest if the content of an SV looks like a number (or is a number).Inf andInfinity are treated as numbers (so will not issue a non-numeric warning), even if youratof() doesn't grok them. Get-magic is ignored.
I32 looks_like_number(SV * const sv)MUTABLE_AVMUTABLE_CVMUTABLE_GVMUTABLE_HVMUTABLE_IOMUTABLE_PTRMUTABLE_SVTheMUTABLE_*() macros cast pointers to the types shown, in such a way (compiler permitting) that casting away const-ness will give a warning; e.g.:
const SV *sv = ...;AV *av1 = (AV*)sv; <== BAD: the const has been silently cast awayAV *av2 = MUTABLE_AV(sv); <== GOOD: it may warnMUTABLE_PTR is the base macro used to derive new casts. The other already-built-in ones return pointers to what their names indicate.
AV * MUTABLE_AV (AV * p)CV * MUTABLE_CV (CV * p)GV * MUTABLE_GV (GV * p)HV * MUTABLE_HV (HV * p)IO * MUTABLE_IO (IO * p)void * MUTABLE_PTR(void * p)SV * MUTABLE_SV (SV * p)newRVnewRV_incThese are identical. They create an RV wrapper for an SV. The reference count for the original SV is incremented.
SV * newRV(SV * const sv)newRV_noincCreates an RV wrapper for an SV. The reference count for the original SV isnot incremented.
SV * newRV_noinc(SV * const tmpRef)newSVCreates a new SV. A non-zerolen parameter indicates the number of bytes of preallocated string space the SV should have. An extra byte for a trailingNUL is also reserved. (SvPOK is not set for the SV even if string space is allocated.) The reference count for the new SV is set to 1.
In 5.9.3,newSV() replaces the olderNEWSV() API, and drops the first parameter,x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option,PERL_MEM_LOG (see"PERL_MEM_LOG" in perlhacktips). The older API is still there for use in XS modules supporting older perls.
SV * newSV(const STRLEN len)newSVboolCreates a new SV boolean.
SV * newSVbool(const bool bool_val)newSV_falseCreates a new SV that is a boolean false.
SV * newSV_false()newSVhekCreates a new SV from the hash key structure. It will generate scalars that point to the shared string table where possible. Returns a new (undefined) SV ifhek is NULL.
SV * newSVhek(const HEK * const hek)newSVhek_mortalCreates a new mortal SV from the hash key structure. It will generate scalars that point to the shared string table where possible. Returns a new (undefined) SV ifhek is NULL.
This is more efficient than using sv_2mortal(newSVhek( ... ))
SV * newSVhek_mortal(const HEK * const hek)newSVivCreates a new SV and copies an integer into it. The reference count for the SV is set to 1.
SV * newSViv(const IV i)newSVnvCreates a new SV and copies a floating point value into it. The reference count for the SV is set to 1.
SV * newSVnv(const NV n)newSVpadnameNOTE:newSVpadname isexperimental and may change or be removed without notice.
Creates a new SV containing the pad name.
SV* newSVpadname(PADNAME *pn)newSVpvCreates a new SV and copies a string (which may containNUL (\0) characters) into it. The reference count for the SV is set to 1. Iflen is zero, Perl will compute the length usingstrlen(), (which means if you use this option, thats can't have embeddedNUL characters and has to have a terminatingNUL byte).
This function can cause reliability issues if you are likely to pass in empty strings that are not null terminated, because it will run strlen on the string and potentially run past valid memory.
Using"newSVpvn" is a safer alternative for nonNUL terminated strings. For string literals use"newSVpvs" instead. This function will work fine forNUL terminated strings, but if you want to avoid the if statement on whether to callstrlen usenewSVpvn instead (callingstrlen yourself).
SV * newSVpv(const char * const s, const STRLEN len)newSVpvfCreates a new SV and initializes it with the string formatted likesv_catpvf.
NOTE:newSVpvf must be explicitly called asPerl_newSVpvf with anaTHX_ parameter.
SV * Perl_newSVpvf(pTHX_ const char * const pat, ...)newSVpvf_nocontextLike"newSVpvf" but does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
SV * newSVpvf_nocontext(const char * const pat, ...)newSVpvnCreates a new SV and copies a string into it, which may containNUL characters (\0) and other binary data. The reference count for the SV is set to 1. Note that iflen is zero, Perl will create a zero length (Perl) string. You are responsible for ensuring that the source buffer is at leastlen bytes long. If thebuffer argument is NULL the new SV will be undefined.
SV * newSVpvn(const char * const buffer, const STRLEN len)newSVpvn_flagsCreates a new SV and copies a string (which may containNUL (\0) characters) into it. The reference count for the SV is set to 1. Note that iflen is zero, Perl will create a zero length string. You are responsible for ensuring that the source string is at leastlen bytes long. If thes argument is NULL the new SV will be undefined. Currently the only flag bits accepted areSVf_UTF8 andSVs_TEMP. IfSVs_TEMP is set, thensv_2mortal() is called on the result before returning. IfSVf_UTF8 is set,s is considered to be in UTF-8 and theSVf_UTF8 flag will be set on the new SV.newSVpvn_utf8() is a convenience wrapper for this function, defined as
#define newSVpvn_utf8(s, len, u)\ newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)SV * newSVpvn_flags(const char * const s, const STRLEN len, const U32 flags)newSVpvn_shareCreates a new SV with itsSvPVX_const pointing to a shared string in the string table. If the string does not already exist in the table, it is created first. Turns on theSvIsCOW flag (orREADONLY andFAKE in 5.16 and earlier). If thehash parameter is non-zero, that value is used; otherwise the hash is computed. The string's hash can later be retrieved from the SV with the"SvSHARED_HASH" macro. The idea here is that as the string table is used for shared hash keys these strings will haveSvPVX_const == HeKEY and hash lookup will avoid string compare.
SV * newSVpvn_share(const char *s, I32 len, U32 hash)newSVpvn_utf8Creates a new SV and copies a string (which may containNUL (\0) characters) into it. Ifutf8 is true, callsSvUTF8_on on the new SV. Implemented as a wrapper aroundnewSVpvn_flags.
SV* newSVpvn_utf8(const char* s, STRLEN len, U32 utf8)newSVpvsLikenewSVpvn, but takes a literal string instead of a string/length pair.
SV* newSVpvs("literal string")newSVpvs_flagsLikenewSVpvn_flags, but takes a literal string instead of a string/length pair.
SV* newSVpvs_flags("literal string", U32 flags)newSVpv_shareLikenewSVpvn_share, but takes aNUL-terminated string instead of a string/length pair.
SV * newSVpv_share(const char *s, U32 hash)newSVpvs_shareLikenewSVpvn_share, but takes a literal string instead of a string/length pair and omits the hash parameter.
SV* newSVpvs_share("literal string")newSVrvCreates a new SV for the existing RV,rv, to point to. Ifrv is not an RV then it will be upgraded to one. Ifclassname is non-null then the new SV will be blessed in the specified package. The new SV is returned and its reference count is 1. The reference count 1 is owned byrv. See also newRV_inc() and newRV_noinc() for creating a new RV properly.
SV * newSVrv(SV * const rv, const char * const classname)newSVsvnewSVsv_flagsnewSVsv_nomgThese create a new SV which is an exact duplicate of the original SV (usingsv_setsv.)
They differ only in thatnewSVsv performs 'get' magic;newSVsv_nomg skips any magic; andnewSVsv_flags allows you to explicitly set aflags parameter.
SV * newSVsv (SV * const old)SV * newSVsv_flags(SV * const old, I32 flags)SV * newSVsv_nomg (SV * const old)newSV_trueCreates a new SV that is a boolean true.
SV * newSV_true()newSV_typeCreates a new SV, of the type specified. The reference count for the new SV is set to 1.
SV * newSV_type(const svtype type)newSV_type_mortalCreates a new mortal SV, of the type specified. The reference count for the new SV is set to 1.
This is equivalent to SV* sv = sv_2mortal(newSV_type(<some type>)) and SV* sv = sv_newmortal(); sv_upgrade(sv, <some_type>) but should be more efficient than both of them. (Unless sv_2mortal is inlined at some point in the future.)
SV * newSV_type_mortal(const svtype type)newSVuvCreates a new SV and copies an unsigned integer into it. The reference count for the SV is set to 1.
SV * newSVuv(const UV u)NullsvNull SV pointer. (No longer available whenPERL_CORE is defined.)
PL_sv_noThis is thefalse SV. It is readonly. See"PL_sv_yes". Always refer to this as&PL_sv_no.
SV PL_sv_noPL_sv_undefThis is theundef SV. It is readonly. Always refer to this as&PL_sv_undef.
SV PL_sv_undefPL_sv_yesThis is thetrue SV. It is readonly. See"PL_sv_no". Always refer to this as&PL_sv_yes.
SV PL_sv_yesPL_sv_zeroThis readonly SV has a zero numeric value and a"0" string value. It's similar to"PL_sv_no" except for its string value. Can be used as a cheap alternative tomXPUSHi(0) for example. Always refer to this as&PL_sv_zero. Introduced in 5.28.
SV PL_sv_zeroSAVE_DEFSVLocalize$_. See"Localizing changes" in perlguts.
void SAVE_DEFSVsortsvIn-place sort an array of SV pointers with the given comparison routine.
Currently this always uses mergesort. See"sortsv_flags" for a more flexible routine.
void sortsv(SV **array, size_t num_elts, SVCOMPARE_t cmp)sortsv_flagsIn-place sort an array of SV pointers with the given comparison routine, with various SORTf_* flag options.
void sortsv_flags(SV **array, size_t num_elts, SVCOMPARE_t cmp, U32 flags)SvAMAGICReturns a boolean as to whethersv has overloading (active magic) enabled or not.
bool SvAMAGIC(SV * sv)SvAMAGIC_offIndicate thatsv has overloading (active magic) disabled.
void SvAMAGIC_off(SV *sv)SvAMAGIC_onIndicate thatsv has overloading (active magic) enabled.
void SvAMAGIC_on(SV *sv)sv_backoffRemove any string offset. You should normally use theSvOOK_off macro wrapper instead.
void sv_backoff(SV * const sv)sv_blessBlesses an SV into a specified package. The SV must be an RV. The package must be designated by its stash (see"gv_stashpv"). The reference count of the SV is unaffected.
SV * sv_bless(SV * const sv, HV * const stash)SvBoolFlagsOKReturns a bool indicating whether the SV has the right flags set such that it is safe to callBOOL_INTERNALS_sv_isbool() orBOOL_INTERNALS_sv_isbool_true() orBOOL_INTERNALS_sv_isbool_false(). Currently equivalent toSvIandPOK(sv) orSvIOK(sv) && SvPOK(sv). Serialization may want to unroll this check. If so you are strongly recommended to add code likeassert(SvBoolFlagsOK(sv));before calling using any of the BOOL_INTERNALS macros.
U32 SvBoolFlagsOK(SV* sv)sv_catpvsv_catpv_flagssv_catpv_mgsv_catpv_nomgThese concatenate theNUL-terminated stringsstr onto the end of the string which is in the SV. If the SV has the UTF-8 status set, then the bytes appended should be valid UTF-8.
They differ only in how they handle magic:
sv_catpv_mg performs both 'get' and 'set' magic.
sv_catpv performs only 'get' magic.
sv_catpv_nomg skips all magic.
sv_catpv_flags has an extraflags parameter which allows you to specify any combination of magic handling (usingSV_GMAGIC and/orSV_SMAGIC), and to also override the UTF-8 handling. By supplying theSV_CATUTF8 flag, the appended string is forced to be interpreted as UTF-8; by supplying instead theSV_CATBYTES flag, it will be interpreted as just bytes. Either the SV or the string appended will be upgraded to UTF-8 if necessary.
void sv_catpv (SV * const dsv, const char *sstr)void sv_catpv_flags(SV *dsv, const char *sstr, const I32 flags)void sv_catpv_mg (SV * const dsv, const char * const sstr)void sv_catpv_nomg (SV * const dsv, const char *sstr)sv_catpvfsv_catpvf_mgsv_catpvf_mg_nocontextsv_catpvf_nocontextThese process their arguments likesprintf, and append the formatted output to an SV. As withsv_vcatpvfn, argument reordering is not supporte when called with a non-null C-style variable argument list.
If the appended data contains "wide" characters (including, but not limited to, SVs with a UTF-8 PV formatted with%s, and characters >255 formatted with%c), the original SV might get upgraded to UTF-8.
If the original SV was UTF-8, the pattern should be valid UTF-8; if the original SV was bytes, the pattern should be too.
All perform 'get' magic, but onlysv_catpvf_mg andsv_catpvf_mg_nocontext perform 'set' magic.
sv_catpvf_nocontext andsv_catpvf_mg_nocontext do not take a thread context (aTHX) parameter, so are used in situations where the caller doesn't already have the thread context.
NOTE:sv_catpvf must be explicitly called asPerl_sv_catpvf with anaTHX_ parameter.
NOTE:sv_catpvf_mg must be explicitly called asPerl_sv_catpvf_mg with anaTHX_ parameter.
void Perl_sv_catpvf (pTHX_ SV * const sv, const char * const pat, ...)void Perl_sv_catpvf_mg (pTHX_ SV * const sv, const char * const pat, ...)void sv_catpvf_mg_nocontext(SV * const sv, const char * const pat, ...)void sv_catpvf_nocontext (SV * const sv, const char * const pat, ...)sv_catpvnsv_catpvn_flagssv_catpvn_mgsv_catpvn_nomgThese concatenate thelen bytes of the string beginning atptr onto the end of the string which is indsv. The caller must make sureptr contains at leastlen bytes.
For all butsv_catpvn_flags, the string appended is assumed to be valid UTF-8 if the SV has the UTF-8 status set, and a string of bytes otherwise.
They differ in that:
sv_catpvn_mg performs both 'get' and 'set' magic ondsv.
sv_catpvn performs only 'get' magic.
sv_catpvn_nomg skips all magic.
sv_catpvn_flags has an extraflags parameter which allows you to specify any combination of magic handling (usingSV_GMAGIC and/orSV_SMAGIC) and to also override the UTF-8 handling. By supplying theSV_CATBYTES flag, the appended string is interpreted as plain bytes; by supplying instead theSV_CATUTF8 flag, it will be interpreted as UTF-8, and thedsv will be upgraded to UTF-8 if necessary.
sv_catpvn,sv_catpvn_mg, andsv_catpvn_nomg are implemented in terms ofsv_catpvn_flags.
void sv_catpvn (SV *dsv, const char *sstr, STRLEN len)void sv_catpvn_flags(SV * const dsv, const char *sstr, const STRLEN len, const I32 flags)void sv_catpvn_mg (SV *dsv, const char *sstr, STRLEN len)void sv_catpvn_nomg (SV *dsv, const char *sstr, STRLEN len)sv_catpvsLikesv_catpvn, but takes a literal string instead of a string/length pair.
void sv_catpvs(SV* sv, "literal string")sv_catpvs_flagsLikesv_catpvn_flags, but takes a literal string instead of a string/length pair.
void sv_catpvs_flags(SV* sv, "literal string", I32 flags)sv_catpvs_mgLikesv_catpvn_mg, but takes a literal string instead of a string/length pair.
void sv_catpvs_mg(SV* sv, "literal string")sv_catpvs_nomgLikesv_catpvn_nomg, but takes a literal string instead of a string/length pair.
void sv_catpvs_nomg(SV* sv, "literal string")sv_catsvsv_catsv_flagssv_catsv_mgsv_catsv_nomgThese concatenate the string from SVsstr onto the end of the string in SVdsv. Ifsstr is null, these are no-ops; otherwise onlydsv is modified.
They differ only in what magic they perform:
sv_catsv_mg performs 'get' magic on both SVs before the copy, and 'set' magic ondsv afterwards.
sv_catsv performs just 'get' magic, on both SVs.
sv_catsv_nomg skips all magic.
sv_catsv_flags has an extraflags parameter which allows you to useSV_GMAGIC and/orSV_SMAGIC to specify any combination of magic handling (although either both or neither SV will have 'get' magic applied to it.)
sv_catsv,sv_catsv_mg, andsv_catsv_nomg are implemented in terms ofsv_catsv_flags.
void sv_catsv (SV *dsv, SV *sstr)void sv_catsv_flags(SV * const dsv, SV * const sstr, const I32 flags)void sv_catsv_mg (SV *dsv, SV *sstr)void sv_catsv_nomg (SV *dsv, SV *sstr)SV_CHECK_THINKFIRSTRemove any encumbrances fromsv, that need to be taken care of before it is modifiable. For example if it is Copy on Write (COW), now is the time to make that copy.
If you know that you are about to change the PV value ofsv, instead use"SV_CHECK_THINKFIRST_COW_DROP" to avoid the write that would be immediately written again.
void SV_CHECK_THINKFIRST(SV * sv)SV_CHECK_THINKFIRST_COW_DROPCall this when you are about to replace the PV value insv, which is potentially copy-on-write. It stops any sharing with other SVs, so that no Copy on Write (COW) actually happens. This COW would be useless, as it would immediately get changed to something else. This function also removes any other encumbrances that would be problematic when changingsv.
void SV_CHECK_THINKFIRST_COW_DROP(SV * sv)sv_chopEfficient removal of characters from the beginning of the string buffer.SvPOK(sv), or at leastSvPOKp(sv), must be true andptr must be a pointer to somewhere inside the string buffer.ptr becomes the first character of the adjusted string. Uses theOOK hack. On return, onlySvPOK(sv) andSvPOKp(sv) among theOK flags will be true.
Beware: after this function returns,ptr and SvPVX_const(sv) may no longer refer to the same chunk of data.
The unfortunate similarity of this function's name to that of Perl'schop operator is strictly coincidental. This function works from the left;chop works from the right.
void sv_chop(SV * const sv, const char * const ptr)sv_clearClear an SV: call any destructors, free up any memory used by the body, and free the body itself. The SV's head isnot freed, although its type is set to all 1's so that it won't inadvertently be assumed to be live during global destruction etc. This function should only be called whenREFCNT is zero. Most of the time you'll want to callSvREFCNT_dec instead.
void sv_clear(SV * const orig_sv)sv_cmpCompares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string insv1 is less than, equal to, or greater than the string insv2. Is UTF-8 and'use bytes' aware, handles get magic, and will coerce its args to strings if necessary. See also"sv_cmp_locale".
I32 sv_cmp(SV * const sv1, SV * const sv2)sv_cmp_flagsCompares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string insv1 is less than, equal to, or greater than the string insv2. Is UTF-8 and'use bytes' aware and will coerce its args to strings if necessary. If the flags has theSV_GMAGIC bit set, it handles get magic. See also"sv_cmp_locale_flags".
I32 sv_cmp_flags(SV * const sv1, SV * const sv2, const U32 flags)sv_cmp_localeCompares the strings in two SVs in a locale-aware manner. Is UTF-8 and'use bytes' aware, handles get magic, and will coerce its args to strings if necessary. See also"sv_cmp".
I32 sv_cmp_locale(SV * const sv1, SV * const sv2)sv_cmp_locale_flagsCompares the strings in two SVs in a locale-aware manner. Is UTF-8 and'use bytes' aware and will coerce its args to strings if necessary. If the flags containSV_GMAGIC, it handles get magic. See also"sv_cmp_flags".
I32 sv_cmp_locale_flags(SV * const sv1, SV * const sv2, const U32 flags)sv_collxfrmThis callssv_collxfrm_flags with the SV_GMAGIC flag. See"sv_collxfrm_flags".
char * sv_collxfrm(SV * const sv, STRLEN * const nxp)sv_collxfrm_flagsAdd Collate Transform magic to an SV if it doesn't already have it. If the flags containSV_GMAGIC, it handles get-magic.
Any scalar variable may carryPERL_MAGIC_collxfrm magic that contains the scalar data of the variable, but transformed to such a format that a normal memory comparison can be used to compare the data according to the locale settings.
char * sv_collxfrm_flags(SV * const sv, STRLEN * const nxp, I32 const flags)sv_copypvsv_copypv_flagssv_copypv_nomgThese copy a stringified representation of the source SV into the destination SV. They automatically perform coercion of numeric values into strings. Guaranteed to preserve theUTF8 flag even from overloaded objects. Similar in nature tosv_2pv[_flags] but they operate directly on an SV instead of just the string. Mostly they use"sv_2pv_flags" to do the work, except when that would lose the UTF-8'ness of the PV.
The three forms differ only in whether or not they perform 'get magic' onsv.sv_copypv_nomg skips 'get magic';sv_copypv performs it; andsv_copypv_flags either performs it (if theSV_GMAGIC bit is set inflags) or doesn't (if that bit is cleared).
void sv_copypv (SV * const dsv, SV * const ssv)void sv_copypv_flags(SV * const dsv, SV * const ssv, const I32 flags)void sv_copypv_nomg (SV * const dsv, SV * const ssv)SvCURReturns the length, in bytes, of the PV inside the SV. Note that this may not match Perl'slength; for that, usesv_len_utf8(sv). See"SvLEN" also.
STRLEN SvCUR(SV* sv)SvCUR_setSets the current length, in bytes, of the C string which is in the SV. See"SvCUR" andSvIV_set>.
void SvCUR_set(SV* sv, STRLEN len)sv_2cvUsing various gambits, try to get a CV from an SV; in addition, try if possible to set*st and*gvp to the stash and GV associated with it. The flags inlref are passed togv_fetchsv.
CV * sv_2cv(SV *sv, HV ** const st, GV ** const gvp, const I32 lref)sv_decsv_dec_nomgThese auto-decrement the value in the SV, doing string to numeric conversion if necessary. They both handle operator overloading.
They differ only in that:
sv_dec handles 'get' magic;sv_dec_nomg skips 'get' magic.
void sv_dec(SV * const sv)sv_derived_fromExactly like"sv_derived_from_pv", but doesn't take aflags parameter.
bool sv_derived_from(SV *sv, const char * const name)sv_derived_from_hvExactly like"sv_derived_from_pvn", but takes the name string as theHvNAME of the given HV (which would presumably represent a stash).
bool sv_derived_from_hv(SV *sv, HV *hv)sv_derived_from_pvExactly like"sv_derived_from_pvn", but takes a nul-terminated string instead of a string/length pair.
bool sv_derived_from_pv(SV *sv, const char * const name, U32 flags)sv_derived_from_pvnReturns a boolean indicating whether the SV is derived from the specified classat the C level. To check derivation at the Perl level, callisa() as a normal Perl method.
Currently, the only significant value forflags is SVf_UTF8.
bool sv_derived_from_pvn(SV *sv, const char * const name, const STRLEN len, U32 flags)sv_derived_from_svExactly like"sv_derived_from_pvn", but takes the name string in the form of an SV instead of a string/length pair. This is the advised form.
bool sv_derived_from_sv(SV *sv, SV *namesv, U32 flags)sv_doesLike"sv_does_pv", but doesn't take aflags parameter.
bool sv_does(SV *sv, const char * const name)sv_does_pvLike"sv_does_sv", but takes a nul-terminated string instead of an SV.
bool sv_does_pv(SV *sv, const char * const name, U32 flags)sv_does_pvnLike"sv_does_sv", but takes a string/length pair instead of an SV.
bool sv_does_pvn(SV *sv, const char * const name, const STRLEN len, U32 flags)sv_does_svReturns a boolean indicating whether the SV performs a specific, named role. The SV can be a Perl object or the name of a Perl class.
bool sv_does_sv(SV *sv, SV *namesv, U32 flags)SvENDReturns a pointer to the spot just after the last character in the string which is in the SV, where there is usually a trailingNUL character (even though Perl scalars do not strictly require it). See"SvCUR". Access the character as*(SvEND(sv)).
Warning: IfSvCUR is equal toSvLEN, thenSvEND points to unallocated memory.
char* SvEND(SV* sv)sv_eqsv_eq_flagsThese each return a boolean indicating whether or not the strings in the two SVs are equal. If'use bytes' is in effect, the comparison is byte-by-byte; otherwise character-by-character. Each will coerce its args to strings if necessary.
They differ only in thatsv_eq always processes get magic, whilesv_eq_flags processes get magic only when theflags parameter has theSV_GMAGIC bit set.
These functions do not handle operator overloading. For versions that do, see instead"sv_streq" or"sv_streq_flags".
I32 sv_eq (SV *sv1, SV *sv2)I32 sv_eq_flags(SV *sv1, SV *sv2, const U32 flags)sv_force_normalUndo various types of fakery on an SV: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to anxpvmg. See also"sv_force_normal_flags".
void sv_force_normal(SV *sv)sv_force_normal_flagsUndo various types of fakery on an SV, where fakery means "more than" a string: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to anxpvmg; if we're a copy-on-write scalar, this is the on-write time when we do the copy, and is also used locally; if this is a vstring, drop the vstring magic. IfSV_COW_DROP_PV is set then a copy-on-write scalar drops its PV buffer (if any) and becomesSvPOK_off rather than making a copy. (Used where this scalar is about to be set to some other value.) In addition, theflags parameter gets passed tosv_unref_flags() when unreffing.sv_force_normal calls this function with flags set to 0.
This function is expected to be used to signal to perl that this SV is about to be written to, and any extra book-keeping needs to be taken care of. Hence, it croaks on read-only values.
void sv_force_normal_flags(SV * const sv, const U32 flags)sv_freeDecrement an SV's reference count, and if it drops to zero, callsv_clear to invoke destructors and free up any memory used by the body; finally, deallocating the SV's head itself. Normally called via a wrapper macroSvREFCNT_dec.
void sv_free(SV * const sv)SvGAMAGICReturns true if the SV has get magic or overloading. If either is true then the scalar is active data, and has the potential to return a new value every time it is accessed. Hence you must be careful to only read it once per user logical operation and work with that returned value. If neither is true then the scalar's value cannot change unless written to.
U32 SvGAMAGIC(SV* sv)sv_get_backrefsNOTE:sv_get_backrefs isexperimental and may change or be removed without notice.
Ifsv is the target of a weak reference then it returns the back references structure associated with the sv; otherwise returnNULL.
When returning a non-null result the type of the return is relevant. If it is an AV then the elements of the AV are the weak reference RVs which point at this item. If it is any other type then the item itself is the weak reference.
See alsoPerl_sv_add_backref(),Perl_sv_del_backref(),Perl_sv_kill_backrefs()
SV * sv_get_backrefs(SV * const sv)SvGETMAGICInvokes"mg_get" on an SV if it has 'get' magic. For example, this will callFETCH on a tied variable. As of 5.37.1, this function is guaranteed to evaluate its argument exactly once.
void SvGETMAGIC(SV *sv)sv_getsGet a line from the filehandle and store it into the SV, optionally appending to the currently-stored string. Ifappend is not 0, the line is appended to the SV instead of overwriting it.append should be set to the byte offset that the appended string should start at in the SV (typically,SvCUR(sv) is a suitable choice).
char * sv_gets(SV * const sv, PerlIO * const fp, I32 append)SvGROWExpands the character buffer in the SV so that it has room for the indicated number of bytes (remember to reserve space for an extra trailingNUL character). Callssv_grow to perform the expansion if necessary. Returns a pointer to the character buffer. SV must be of type >=SVt_PV. One alternative is to callsv_grow if you are not sure of the type of SV.
You might mistakenly think thatlen is the number of bytes to add to the existing size, but instead it is the total sizesv should be.
char * SvGROW(SV* sv, STRLEN len)SvIandPOKReturns a bool indicating whether the SV is bothSvPOK() andSvIOK() at the same time. Equivalent toSvIOK(sv) && SvPOK(sv) but more efficient.
U32 SvIandPOK(SV* sv)SvIandPOK_offUnsets the PV and IV status of an SV in one operation. Equivalent toSvIOK_off(sv); SvPK_off(v); but more efficient.
void SvIandPOK_off(SV* sv)SvIandPOK_onTells an SV that is a string and a number in one operation. Equivalent toSvIOK_on(sv); SvPOK_on(sv); but more efficient.
void SvIandPOK_on(SV* sv)sv_incsv_inc_nomgThese auto-increment the value in the SV, doing string to numeric conversion if necessary. They both handle operator overloading.
They differ only in thatsv_inc performs 'get' magic;sv_inc_nomg skips any magic.
void sv_inc(SV * const sv)sv_insertsv_insert_flagsThese insert and/or replace a string at the specified offset/length within the SV. Similar to the Perlsubstr() function, withlittlelen bytes starting atlittle replacinglen bytes of the string inbigstr starting atoffset. They handle get magic.
sv_insert_flags is identical to plainsv_insert, but the extraflags are passed to theSvPV_force_flags operation that is internally applied tobigstr.
void sv_insert (SV * const bigstr, const STRLEN offset, const STRLEN len, const char * const little, const STRLEN littlelen)void sv_insert_flags(SV * const bigstr, const STRLEN offset, const STRLEN len, const char *little, const STRLEN littlelen, const U32 flags)sv_2ioUsing various gambits, try to get an IO from an SV: the IO slot if its a GV; or the recursive result if we're an RV; or the IO slot of the symbol named after the PV if we're a string.
'Get' magic is ignored on thesv passed in, but will be called onSvRV(sv) ifsv is an RV.
IO * sv_2io(SV * const sv)SvIOKReturns a U32 value indicating whether the SV contains an integer.
U32 SvIOK(SV* sv)SvIOK_notUVReturns a boolean indicating whether the SV contains a signed integer.
bool SvIOK_notUV(SV* sv)SvIOK_offUnsets the IV status of an SV.
void SvIOK_off(SV* sv)SvIOK_onTells an SV that it is an integer.
void SvIOK_on(SV* sv)SvIOK_onlyTells an SV that it is an integer and disables all otherOK bits.
void SvIOK_only(SV* sv)SvIOK_only_UVTells an SV that it is an unsigned integer and disables all otherOK bits.
void SvIOK_only_UV(SV* sv)SvIOKpReturns a U32 value indicating whether the SV contains an integer. Checks theprivate setting. UseSvIOK instead.
U32 SvIOKp(SV* sv)SvIOK_UVReturns a boolean indicating whether the SV contains an integer that must be interpreted as unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be flagged as eitherSvUOK orSvIOK.
bool SvIOK_UV(SV* sv)sv_isaReturns a boolean indicating whether the SV is blessed into the specified class.
This does not check for subtypes or method overloading. Usesv_isa_sv to verify an inheritance relationship in the same way as theisa operator by respecting anyisa() method overloading; orsv_derived_from_sv to test directly on the actual object type.
int sv_isa(SV *sv, const char * const name)sv_isa_svReturns a boolean indicating whether the SV is an object reference and is derived from the specified class, respecting anyisa() method overloading it may have. Returns false ifsv is not a reference to an object, or is not derived from the specified class.
This is the function used to implement the behaviour of theisa operator.
Does not invoke magic onsv.
Not to be confused with the oldersv_isa function, which does not use an overloadedisa() method, nor will check subclassing.
bool sv_isa_sv(SV *sv, SV *namesv)SvIsBOOLReturns true if the SV is one of the special boolean constants (PL_sv_yes or PL_sv_no), or is a regular SV whose last assignment stored a copy of one.
bool SvIsBOOL(SV* sv)SvIsCOWReturns a U32 value indicating whether the SV is Copy-On-Write (either shared hash key scalars, or full Copy On Write scalars if 5.9.0 is configured for COW).
U32 SvIsCOW(SV* sv)SvIsCOW_shared_hashReturns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.
bool SvIsCOW_shared_hash(SV* sv)sv_isobjectReturns a boolean indicating whether the SV is an RV pointing to a blessed object. If the SV is not an RV, or if the object is not blessed, then this will return false.
int sv_isobject(SV *sv)SvIVSvIV_nomgSvIVxThese each coerce the given SV to IV and return it. The returned value in many circumstances will get stored insv's IV slot, but not in all cases. (Use"sv_setiv" to make sure it does).
As of 5.37.1, all are guaranteed to evaluatesv only once.
SvIVx is now identical toSvIV, but prior to 5.37.1, it was the only form guaranteed to evaluatesv only once.
SvIV_nomg is the same asSvIV, but does not perform 'get' magic.
IV SvIV(SV *sv)sv_2iv_flagsReturn the integer value of an SV, doing any necessary string conversion. Ifflags has theSV_GMAGIC bit set, does anmg_get() first. Normally used via theSvIV(sv) andSvIVx(sv) macros.
IV sv_2iv_flags(SV * const sv, const I32 flags)SvIV_setSet the value of the IV pointer in sv to val. It is possible to perform the same function of this macro with an lvalue assignment toSvIVX. With future Perls, however, it will be more efficient to useSvIV_set instead of the lvalue assignment toSvIVX.
void SvIV_set(SV* sv, IV val)SvIVXReturns the raw value in the SV's IV slot, without checks or conversions. Only use when you are sureSvIOK is true. See also"SvIV".
IV SvIVX(SV* sv)SvLENReturns the size of the string buffer in the SV, not including any part attributable toSvOOK. See"SvCUR".
STRLEN SvLEN(SV* sv)sv_lenReturns the length of the string in the SV. Handles magic and type coercion and sets the UTF8 flag appropriately. See also"SvCUR", which gives raw access to thexpv_cur slot.
STRLEN sv_len(SV * const sv)SvLEN_setSet the size of the string buffer for the SV. See"SvLEN".
void SvLEN_set(SV* sv, STRLEN len)sv_len_utf8sv_len_utf8_nomgThese return the number of characters in the string in an SV, counting wide UTF-8 bytes as a single character. Both handle type coercion. They differ only in thatsv_len_utf8 performs 'get' magic;sv_len_utf8_nomg skips any magic.
STRLEN sv_len_utf8(SV * const sv)SvLOCKArranges for a mutual exclusion lock to be obtained onsv if a suitable module has been loaded.
void SvLOCK(SV* sv)sv_magicAdds magic to an SV. First upgradessv to typeSVt_PVMG if necessary, then adds a new magic item of typehow to the head of the magic list.
See"sv_magicext" (whichsv_magic now calls) for a description of the handling of thename andnamlen arguments.
You need to usesv_magicext to add magic toSvREADONLY SVs and also to add more than one instance of the samehow.
void sv_magic(SV * const sv, SV * const obj, const int how, const char * const name, const I32 namlen)sv_magicextAdds magic to an SV, upgrading it if necessary. Applies the suppliedvtable and returns a pointer to the magic added.
Note thatsv_magicext will allow things thatsv_magic will not. In particular, you can add magic toSvREADONLY SVs, and add more than one instance of the samehow.
Ifnamlen is greater than zero then asavepvncopy ofname is stored, ifnamlen is zero thenname is stored as-is and - as another special case - if(name && namlen == HEf_SVKEY) thenname is assumed to contain an SV* and is stored as-is with itsREFCNT incremented.
(This is now used as a subroutine bysv_magic.)
MAGIC * sv_magicext(SV * const sv, SV * const obj, const int how, const MGVTBL * const vtbl, const char * const name, const I32 namlen)SvMAGIC_setSet the value of the MAGIC pointer insv to val. See"SvIV_set".
void SvMAGIC_set(SV* sv, MAGIC* val)sv_2mortalMarks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call toFREETMPS, or by an implicit call at places such as statement boundaries.SvTEMP() is turned on which means that the SV's string buffer can be "stolen" if this SV is copied. See also"sv_newmortal" and"sv_mortalcopy".
SV * sv_2mortal(SV * const sv)sv_mortalcopyCreates a new SV which is a copy of the original SV (usingsv_setsv). The new SV is marked as mortal. It will be destroyed "soon", either by an explicit call toFREETMPS, or by an implicit call at places such as statement boundaries. See also"sv_newmortal" and"sv_2mortal".
SV * sv_mortalcopy(SV * const oldsv)sv_mortalcopy_flagsLikesv_mortalcopy, but the extraflags are passed to thesv_setsv_flags.
SV * sv_mortalcopy_flags(SV * const oldsv, U32 flags)sv_newmortalCreates a new null SV which is mortal. The reference count of the SV is set to 1. It will be destroyed "soon", either by an explicit call toFREETMPS, or by an implicit call at places such as statement boundaries. See also"sv_mortalcopy" and"sv_2mortal".
SV * sv_newmortal()SvNIOKReturns a U32 value indicating whether the SV contains a number, integer or double.
U32 SvNIOK(SV* sv)SvNIOK_offUnsets the NV/IV status of an SV.
void SvNIOK_off(SV* sv)SvNIOKpReturns a U32 value indicating whether the SV contains a number, integer or double. Checks theprivate setting. UseSvNIOK instead.
U32 SvNIOKp(SV* sv)SvNOKReturns a U32 value indicating whether the SV contains a double.
U32 SvNOK(SV* sv)SvNOK_offUnsets the NV status of an SV.
void SvNOK_off(SV* sv)SvNOK_onTells an SV that it is a double.
void SvNOK_on(SV* sv)SvNOK_onlyTells an SV that it is a double and disables all other OK bits.
void SvNOK_only(SV* sv)SvNOKpReturns a U32 value indicating whether the SV contains a double. Checks theprivate setting. UseSvNOK instead.
U32 SvNOKp(SV* sv)sv_nolockingDEPRECATED! It is planned to removesv_nolocking from a future release of Perl. Do not use it for new code; remove it from existing code.
Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test for aNULL function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" bysv_nosharing().
void sv_nolocking(SV *sv)sv_nounlockingDEPRECATED! It is planned to removesv_nounlocking from a future release of Perl. Do not use it for new code; remove it from existing code.
Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid test for aNULL function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" bysv_nosharing().
void sv_nounlocking(SV *sv)sv_numeqA convenient shortcut for callingsv_numeq_flags with theSV_GMAGIC flag. This function basically behaves like the Perl code$sv1 == $sv2.
bool sv_numeq(SV *sv1, SV *sv2)sv_numeq_flagsReturns a boolean indicating whether the numbers in the two SVs are identical. If the flags argument has theSV_GMAGIC bit set, it handles get-magic too. Will coerce its args to numbers if necessary. TreatsNULL as undef.
If flags does not have theSV_SKIP_OVERLOAD bit set, an attempt to use== overloading will be made. If such overloading does not exist or the flag is set, then regular numerical comparison will be used instead.
bool sv_numeq_flags(SV *sv1, SV *sv2, const U32 flags)SvNVSvNV_nomgSvNVxThese each coerce the given SV to NV and return it. The returned value in many circumstances will get stored insv's NV slot, but not in all cases. (Use"sv_setnv" to make sure it does).
As of 5.37.1, all are guaranteed to evaluatesv only once.
SvNVx is now identical toSvNV, but prior to 5.37.1, it was the only form guaranteed to evaluatesv only once.
SvNV_nomg is the same asSvNV, but does not perform 'get' magic.
NV SvNV(SV *sv)sv_2nv_flagsReturn the num value of an SV, doing any necessary string or integer conversion. Ifflags has theSV_GMAGIC bit set, does anmg_get() first. Normally used via theSvNV(sv) andSvNVx(sv) macros.
NV sv_2nv_flags(SV * const sv, const I32 flags)SvNV_setSet the value of the NV pointer insv to val. See"SvIV_set".
void SvNV_set(SV* sv, NV val)SvNVXReturns the raw value in the SV's NV slot, without checks or conversions. Only use when you are sureSvNOK is true. See also"SvNV".
NV SvNVX(SV* sv)SvOKReturns a U32 value indicating whether the value is defined. This is only meaningful for scalars.
U32 SvOK(SV* sv)SvOOKReturns a U32 indicating whether the pointer to the string buffer is offset. This hack is used internally to speed up removal of characters from the beginning of a"SvPV". WhenSvOOK is true, then the start of the allocated string buffer is actuallySvOOK_offset() bytes beforeSvPVX. This offset used to be stored inSvIVX, but is now stored within the spare part of the buffer.
U32 SvOOK(SV* sv)SvOOK_offRemove any string offset.
void SvOOK_off(SV * sv)SvOOK_offsetReads intolen the offset fromSvPVX back to the true start of the allocated buffer, which will be non-zero ifsv_chop has been used to efficiently remove characters from start of the buffer. Implemented as a macro, which takes the address oflen, which must be of typeSTRLEN. Evaluatessv more than once. Setslen to 0 ifSvOOK(sv) is false.
void SvOOK_offset(SV*sv, STRLEN len)SvPOKReturns a U32 value indicating whether the SV contains a character string.
U32 SvPOK(SV* sv)SvPOK_offUnsets the PV status of an SV.
void SvPOK_off(SV* sv)SvPOK_onTells an SV that it is a string.
void SvPOK_on(SV* sv)SvPOK_onlyTells an SV that it is a string and disables all otherOK bits. Will also turn off the UTF-8 status.
void SvPOK_only(SV* sv)SvPOK_only_UTF8Tells an SV that it is a string and disables all otherOK bits, and leaves the UTF-8 status as it was.
void SvPOK_only_UTF8(SV* sv)SvPOKpReturns a U32 value indicating whether the SV contains a character string. Checks theprivate setting. UseSvPOK instead.
U32 SvPOKp(SV* sv)sv_pos_b2uConverts the value pointed to byoffsetp from a count of bytes from the start of the string, to a count of the equivalent number of UTF-8 chars. Handles magic and type coercion.
Usesv_pos_b2u_flags in preference, which correctly handles strings longer than 2Gb.
void sv_pos_b2u(SV * const sv, I32 * const offsetp)sv_pos_b2u_flagsConvertsoffset from a count of bytes from the start of the string, to a count of the equivalent number of UTF-8 chars. Handles type coercion.flags is passed toSvPV_flags, and usually should beSV_GMAGIC|SV_CONST_RETURN to handle magic.
STRLEN sv_pos_b2u_flags(SV * const sv, STRLEN const offset, U32 flags)sv_pos_u2bConverts the value pointed to byoffsetp from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; iflenp is non-zero, it does the same tolenp, but this time starting from the offset, rather than from the start of the string. Handles magic and type coercion.
Usesv_pos_u2b_flags in preference, which correctly handles strings longer than 2Gb.
void sv_pos_u2b(SV * const sv, I32 * const offsetp, I32 * const lenp)sv_pos_u2b_flagsConverts the offset from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; iflenp is non-zero, it does the same tolenp, but this time starting fromoffset, rather than from the start of the string. Handles type coercion.flags is passed toSvPV_flags, and usually should beSV_GMAGIC|SV_CONST_RETURN to handle magic.
STRLEN sv_pos_u2b_flags(SV * const sv, STRLEN uoffset, STRLEN * const lenp, U32 flags)SvPVSvPV_constSvPV_flagsSvPV_flags_constSvPV_flags_mutableSvPV_mutableSvPV_nolenSvPV_nolen_constSvPV_nomgSvPV_nomg_constSvPV_nomg_const_nolenSvPV_nomg_nolenSvPVbyteSvPVbyte_nolenSvPVbyte_nomgSvPVbyte_or_nullSvPVbyte_or_null_nomgSvPVbytexSvPVbytex_nolenSvPVutf8SvPVutf8_nolenSvPVutf8_nomgSvPVutf8_or_nullSvPVutf8_or_null_nomgSvPVutf8xSvPVxSvPVx_constSvPVx_nolenSvPVx_nolen_constThese each return a pointer to the string insv, or a stringified form ofsv if it does not contain a string. The SV may cache the stringified version becomingSvPOK.
This is a very basic and common operation, so there are lots of slightly different versions of it.
Note that there is no guarantee that the return value ofSvPV(sv), for example, is equal toSvPVX(sv), or thatSvPVX(sv) contains valid data, or that successive calls toSvPV(sv) (or another of these forms) will return the same pointer value each time. This is due to the way that things like overloading and Copy-On-Write are handled. In these cases, the return value may point to a temporary buffer or similar. If you absolutely need theSvPVX field to be valid (for example, if you intend to write to it), then see"SvPV_force".
The differences between the forms are:
The forms with neitherbyte norutf8 in their names (e.g.,SvPV orSvPV_nolen) can expose the SV's internal string buffer. If that buffer consists entirely of bytes 0-255 and includes any bytes above 127, then youMUST consultSvUTF8 to determine the actual code points the string is meant to contain. Generally speaking, it is probably safer to preferSvPVbyte,SvPVutf8, and the like. See"How do I pass a Perl string to a C library?" in perlguts for more details.
The forms withflags in their names allow you to use theflags parameter to specify to process 'get' magic (by setting theSV_GMAGIC flag) or to skip 'get' magic (by clearing it). The other forms process 'get' magic, except for the ones withnomg in their names, which skip 'get' magic.
The forms that take alen parameter will set that variable to the byte length of the resultant string (these are macros, so don't use&len).
The forms withnolen in their names indicate they don't have alen parameter. They should be used only when it is known that the PV is a C string, terminated by a NUL byte, and without intermediate NUL characters; or when you don't care about its length.
The forms withconst in their names returnconst char * so that the compiler will hopefully complain if you were to try to modify the contents of the string (unless you cast away const yourself).
The other forms return a mutable pointer so that the string is modifiable by the caller; this is emphasized for the ones withmutable in their names.
As of 5.38, all forms are guaranteed to evaluatesv exactly once. For earlier Perls, use a form whose name ends withx for single evaluation.
SvPVutf8 is likeSvPV, but convertssv to UTF-8 first if not already UTF-8. Similarly, the other forms withutf8 in their names correspond to their respective forms without.
SvPVutf8_or_null andSvPVutf8_or_null_nomg don't have corresponding non-utf8 forms. Instead they are likeSvPVutf8_nomg, but whensv is undef, they returnNULL.
SvPVbyte is likeSvPV, but convertssv to byte representation first if currently encoded as UTF-8. Ifsv cannot be downgraded from UTF-8, it croaks. Similarly, the other forms withbyte in their names correspond to their respective forms without.
SvPVbyte_or_null doesn't have a corresponding non-byte form. Instead it is likeSvPVbyte, but whensv is undef, it returnsNULL.
char* SvPV (SV* sv, STRLEN len)const char* SvPV_const (SV* sv, STRLEN len)char* SvPV_flags (SV* sv, STRLEN len, U32 flags)const char* SvPV_flags_const (SV* sv, STRLEN len, U32 flags)char* SvPV_flags_mutable (SV* sv, STRLEN len, U32 flags)char* SvPV_mutable (SV* sv, STRLEN len)char* SvPV_nolen (SV* sv)const char* SvPV_nolen_const (SV* sv)char* SvPV_nomg (SV* sv, STRLEN len)const char* SvPV_nomg_const (SV* sv, STRLEN len)const char* SvPV_nomg_const_nolen(SV* sv)char* SvPV_nomg_nolen (SV* sv)char* SvPVbyte (SV* sv, STRLEN len)char* SvPVbyte_nolen (SV* sv)char* SvPVbyte_nomg (SV* sv, STRLEN len)char* SvPVbyte_or_null (SV* sv, STRLEN len)char* SvPVbyte_or_null_nomg(SV* sv, STRLEN len)char* SvPVbytex (SV* sv, STRLEN len)char* SvPVbytex_nolen (SV* sv)char* SvPVutf8 (SV* sv, STRLEN len)char* SvPVutf8_nolen (SV* sv)char* SvPVutf8_nomg (SV* sv, STRLEN len)char* SvPVutf8_or_null (SV* sv, STRLEN len)char* SvPVutf8_or_null_nomg(SV* sv, STRLEN len)char* SvPVutf8x (SV* sv, STRLEN len)char* SvPVx (SV* sv, STRLEN len)const char* SvPVx_const (SV* sv, STRLEN len)char* SvPVx_nolen (SV* sv)const char* SvPVx_nolen_const (SV* sv)sv_2pvsv_2pv_flagsThese implement the various forms of the"SvPV" in perlapi macros. The macros are the preferred interface.
These return a pointer to the string value of an SV (coercing it to a string if necessary), and set*lp to its length in bytes.
The forms differ in that plainsv_2pvbyte always processes 'get' magic; andsv_2pvbyte_flags processes 'get' magic if and only ifflags containsSV_GMAGIC.
char * sv_2pv (SV *sv, STRLEN *lp)char * sv_2pv_flags(SV * const sv, STRLEN * const lp, const U32 flags)sv_2pvbytesv_2pvbyte_flagsThese implement the various forms of the"SvPVbyte" in perlapi macros. The macros are the preferred interface.
These return a pointer to the byte-encoded representation of the SV, and set*lp to its length. If the SV is marked as being encoded as UTF-8, it will be downgraded, if possible, to a byte string. If the SV cannot be downgraded, they croak.
The forms differ in that plainsv_2pvbyte always processes 'get' magic; andsv_2pvbyte_flags processes 'get' magic if and only ifflags containsSV_GMAGIC.
char * sv_2pvbyte (SV *sv, STRLEN * const lp)char * sv_2pvbyte_flags(SV *sv, STRLEN * const lp, const U32 flags)SvPVCLEAREnsures that sv is a SVt_PV and that its SvCUR is 0, and that it is properly null terminated. Equivalent to sv_setpvs(""), but more efficient.
char * SvPVCLEAR(SV* sv)SvPVCLEAR_FRESHLike SvPVCLEAR, but optimized for newly-minted SVt_PV/PVIV/PVNV/PVMG that already have a PV buffer allocated, but no SvTHINKFIRST.
char * SvPVCLEAR_FRESH(SV* sv)SvPV_forceSvPV_force_flagsSvPV_force_flags_mutableSvPV_force_flags_nolenSvPV_force_mutableSvPV_force_nolenSvPV_force_nomgSvPV_force_nomg_nolenSvPVbyte_forceSvPVbytex_forceSvPVutf8_forceSvPVutf8x_forceSvPVx_forceThese are like"SvPV", returning the string in the SV, but will force the SV into containing a string ("SvPOK"), and only a string ("SvPOK_only"), by hook or by crook. You need to use one of theseforce routines if you are going to update the"SvPVX" directly.
Note that coercing an arbitrary scalar into a plain PV will potentially strip useful data from it. For example if the SV wasSvROK, then the referent will have its reference count decremented, and the SV itself may be converted to anSvPOK scalar with a string buffer containing a value such as"ARRAY(0x1234)".
The differences between the forms are:
The forms withflags in their names allow you to use theflags parameter to specify to perform 'get' magic (by setting theSV_GMAGIC flag) or to skip 'get' magic (by clearing it). The other forms do perform 'get' magic, except for the ones withnomg in their names, which skip 'get' magic.
The forms that take alen parameter will set that variable to the byte length of the resultant string (these are macros, so don't use&len).
The forms withnolen in their names indicate they don't have alen parameter. They should be used only when it is known that the PV is a C string, terminated by a NUL byte, and without intermediate NUL characters; or when you don't care about its length.
The forms withmutable in their names are effectively the same as those without, but the name emphasizes that the string is modifiable by the caller, which it is in all the forms.
SvPVutf8_force is likeSvPV_force, but convertssv to UTF-8 first if not already UTF-8.
SvPVutf8x_force is likeSvPVutf8_force, but guarantees to evaluatesv only once; use the more efficientSvPVutf8_force otherwise.
SvPVbyte_force is likeSvPV_force, but convertssv to byte representation first if currently encoded as UTF-8. If the SV cannot be downgraded from UTF-8, this croaks.
SvPVbytex_force is likeSvPVbyte_force, but guarantees to evaluatesv only once; use the more efficientSvPVbyte_force otherwise.
char* SvPV_force (SV* sv, STRLEN len)char* SvPV_force_flags (SV * sv, STRLEN len, U32 flags)char* SvPV_force_flags_mutable(SV * sv, STRLEN len, U32 flags)char* SvPV_force_flags_nolen (SV * sv, U32 flags)char* SvPV_force_mutable (SV * sv, STRLEN len)char* SvPV_force_nolen (SV* sv)char* SvPV_force_nomg (SV* sv, STRLEN len)char* SvPV_force_nomg_nolen (SV * sv)char* SvPVbyte_force (SV * sv, STRLEN len)char* SvPVbytex_force (SV * sv, STRLEN len)char* SvPVutf8_force (SV * sv, STRLEN len)char* SvPVutf8x_force (SV * sv, STRLEN len)char* SvPVx_force (SV* sv, STRLEN len)SvPV_freeFrees the PV buffer insv, leaving things in a precarious state, so should only be used as part of a larger operation
void SvPV_free(SV * sv)sv_pvn_force_flagsGet a sensible string out of the SV somehow. Ifflags has theSV_GMAGIC bit set, will"mg_get" onsv if appropriate, else not.sv_pvn_force andsv_pvn_force_nomg are implemented in terms of this function. You normally want to use the various wrapper macros instead: see"SvPV_force" and"SvPV_force_nomg".
char * sv_pvn_force_flags(SV * const sv, STRLEN * const lp, const U32 flags)SvPV_renewLow level micro optimization of"SvGROW". It is generally better to useSvGROW instead. This is becauseSvPV_renew ignores potential issues thatSvGROW handles.sv needs to have a realPV that is unencumbered by things like COW. UsingSV_CHECK_THINKFIRST orSV_CHECK_THINKFIRST_COW_DROP before calling this should clean it up, but why not just useSvGROW if you're not sure about the provenance?
void SvPV_renew(SV* sv, STRLEN len)SvPV_setThis is probably not what you want to use, you probably wanted"sv_usepvn_flags" or"sv_setpvn" or"sv_setpvs".
Set the value of the PV pointer insv to the Perl allocatedNUL-terminated stringval. See also"SvIV_set".
Remember to free the previous PV buffer. There are many things to check. Beware that the existing pointer may be involved in copy-on-write or other mischief, so doSvOOK_off(sv) and usesv_force_normal orSvPV_force (or check theSvIsCOW flag) first to make sure this modification is safe. Then finally, if it is not a COW, call"SvPV_free" to free the previous PV buffer.
void SvPV_set(SV* sv, char* val)SvPV_shrink_to_curTrim any trailing unused memory in the PV ofsv, which needs to have a realPV that is unencumbered by things like COW. Think first before using this functionality. Is the space saving really worth giving up COW? Will the needed size ofsv stay the same?
If the answers are both yes, then use"SV_CHECK_THINKFIRST" or"SV_CHECK_THINKFIRST_COW_DROP" before calling this.
void SvPV_shrink_to_cur(SV* sv)sv_2pvutf8sv_2pvutf8_flagsThese implement the various forms of the"SvPVutf8" in perlapi macros. The macros are the preferred interface.
These return a pointer to the UTF-8-encoded representation of the SV, and set*lp to its length in bytes. They may cause the SV to be upgraded to UTF-8 as a side-effect.
The forms differ in that plainsv_2pvutf8 always processes 'get' magic; andsv_2pvutf8_flags processes 'get' magic if and only ifflags containsSV_GMAGIC.
char * sv_2pvutf8 (SV *sv, STRLEN * const lp)char * sv_2pvutf8_flags(SV *sv, STRLEN * const lp, const U32 flags)SvPVXSvPVX_constSvPVX_mutableSvPVXxThese return a pointer to the physical string in the SV. The SV must contain a string. Prior to 5.9.3 it is not safe to execute these unless the SV's type >=SVt_PV.
These are also used to store the name of an autoloaded subroutine in an XS AUTOLOAD routine. See"Autoloading with XSUBs" in perlguts.
SvPVXx is identical toSvPVX.
SvPVX_mutable is merely a synonym forSvPVX, but its name emphasizes that the string is modifiable by the caller.
SvPVX_const differs in that the return value has been cast so that the compiler will complain if you were to try to modify the contents of the string, (unless you cast away const yourself).
char* SvPVX (SV* sv)const char* SvPVX_const (SV* sv)char* SvPVX_mutable(SV* sv)char* SvPVXx (SV* sv)SvPVXtrueReturns a boolean as to whether or notsv contains a PV that is considered TRUE. FALSE is returned ifsv doesn't contain a PV, or if the PV it does contain is zero length, or consists of just the single character '0'. Every other PV value is considered TRUE.
As of Perl v5.37.1,sv is evaluated exactly once; in earlier releases, it could be evaluated more than once.
bool SvPVXtrue(SV *sv)SvREADONLYReturns true if the argument is readonly, otherwise returns false. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY(SV* sv)SvREADONLY_offMark an object as not-readonly. Exactly what this mean depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_off(SV* sv)SvREADONLY_onMark an object as readonly. Exactly what this means depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_on(SV* sv)sv_refReturns a SV describing what the SV passed in is a reference to.
dst can be a SV to be set to the description or NULL, in which case a mortal SV is returned.
If ob is true and the SV is blessed, the description is the class name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
SV * sv_ref(SV *dst, const SV * const sv, const int ob)SvREFCNTReturns the value of the object's reference count. Exposed to perl code via Internals::SvREFCNT().
U32 SvREFCNT(SV* sv)SvREFCNT_decSvREFCNT_dec_set_NULLSvREFCNT_dec_ret_NULLSvREFCNT_dec_NNThese decrement the reference count of the given SV.
SvREFCNT_dec_NN may only be used whensv is known to not beNULL.
The functionSvREFCNT_dec_ret_NULL() is identical to theSvREFCNT_dec() except it returns a NULLSV *. It is used bySvREFCNT_dec_set_NULL() which is a macro which will, when passed a non-NULL argument, decrement the reference count of its argument and then set it to NULL. You can replace code of the following form:
if (sv) { SvREFCNT_dec_NN(sv); sv = NULL;}with
SvREFCNT_dec_set_NULL(sv);void SvREFCNT_dec (SV *sv)void SvREFCNT_dec_set_NULL(SV *sv)SV * SvREFCNT_dec_ret_NULL(SV *sv)void SvREFCNT_dec_NN (SV *sv)SvREFCNT_incSvREFCNT_inc_NNSvREFCNT_inc_simpleSvREFCNT_inc_simple_NNSvREFCNT_inc_simple_voidSvREFCNT_inc_simple_void_NNSvREFCNT_inc_voidSvREFCNT_inc_void_NNThese all increment the reference count of the given SV. The ones withoutvoid in their names return the SV.
SvREFCNT_inc is the base operation; the rest are optimizations if various input constraints are known to be true; hence, all can be replaced withSvREFCNT_inc.
SvREFCNT_inc_NN can only be used if you knowsv is notNULL. Since we don't have to check the NULLness, it's faster and smaller.
SvREFCNT_inc_void can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
SvREFCNT_inc_void_NN can only be used if you both don't need the return value, and you know thatsv is notNULL. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
SvREFCNT_inc_simple can only be used with expressions without side effects. Since we don't have to store a temporary value, it's faster.
SvREFCNT_inc_simple_NN can only be used with expressions without side effects and you knowsv is notNULL. Since we don't have to store a temporary value, nor check for NULLness, it's faster and smaller.
SvREFCNT_inc_simple_void can only be used with expressions without side effects and you don't need the return value.
SvREFCNT_inc_simple_void_NN can only be used with expressions without side effects, you don't need the return value, and you knowsv is notNULL.
SV * SvREFCNT_inc (SV *sv)SV * SvREFCNT_inc_NN (SV *sv)SV* SvREFCNT_inc_simple (SV* sv)SV* SvREFCNT_inc_simple_NN (SV* sv)void SvREFCNT_inc_simple_void (SV* sv)void SvREFCNT_inc_simple_void_NN(SV* sv)void SvREFCNT_inc_void (SV *sv)void SvREFCNT_inc_void_NN (SV* sv)sv_reftypeReturns a string describing what the SV is a reference to.
If ob is true and the SV is blessed, the string is the class name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
const char * sv_reftype(const SV * const sv, const int ob)sv_replaceMake the first argument a copy of the second, then delete the original. The target SV physically takes over ownership of the body of the source SV and inherits its flags; however, the target keeps any magic it owns, and any magic in the source is discarded. Note that this is a rather specialist SV copying operation; most of the time you'll want to usesv_setsv or one of its many macro front-ends.
void sv_replace(SV * const sv, SV * const nsv)sv_report_usedDump the contents of all SVs not yet freed (debugging aid).
void sv_report_used()sv_resetUnderlying implementation for thereset Perl function. Note that the perl-level function is vaguely deprecated.
void sv_reset(const char *s, HV * const stash)SvROKTests if the SV is an RV.
U32 SvROK(SV* sv)SvROK_offUnsets the RV status of an SV.
void SvROK_off(SV* sv)SvROK_onTells an SV that it is an RV.
void SvROK_on(SV* sv)SvRVDereferences an RV to return the SV.
SV* SvRV(SV* sv)SvRV_setSet the value of the RV pointer insv to val. See"SvIV_set".
void SvRV_set(SV* sv, SV* val)sv_rvunweakenUnweaken a reference: Clear theSvWEAKREF flag on this RV; remove the backreference to this RV from the array of backreferences associated with the target SV, increment the refcount of the target. Silently ignoresundef and warns on non-weak references.
SV * sv_rvunweaken(SV * const sv)sv_rvweakenWeaken a reference: set theSvWEAKREF flag on this RV; give the referred-to SVPERL_MAGIC_backref magic if it hasn't already; and push a back-reference to this RV onto the array of backreferences associated with that magic. If the RV is magical, set magic will be called after the RV is cleared. Silently ignoresundef and warns on already-weak references.
SV * sv_rvweaken(SV * const sv)sv_setboolsv_setbool_mgThese set an SV to a true or false boolean value, upgrading first if necessary.
They differ only in thatsv_setbool_mg handles 'set' magic;sv_setbool does not.
void sv_setbool(SV *sv, bool b)sv_set_boolEquivalent tosv_setsv(sv, bool_val ? &Pl_sv_yes : &PL_sv_no), but may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is$sv = !!$expr;.
Introduced in perl 5.35.11.
void sv_set_bool(SV *sv, const bool bool_val)sv_set_falseEquivalent tosv_setsv(sv, &PL_sv_no), but may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is$sv = !1;.
Introduced in perl 5.35.11.
void sv_set_false(SV *sv)sv_setivsv_setiv_mgThese copy an integer into the given SV, upgrading first if necessary.
They differ only in thatsv_setiv_mg handles 'set' magic;sv_setiv does not.
void sv_setiv (SV * const sv, const IV num)void sv_setiv_mg(SV * const sv, const IV i)SvSETMAGICInvokes"mg_set" on an SV if it has 'set' magic. This is necessary after modifying a scalar, in case it is a magical variable like$| or a tied variable (it callsSTORE). This macro evaluates its argument more than once.
void SvSETMAGIC(SV* sv)SvSetMagicSVSvSetMagicSV_nostealSvSetSVSvSetSV_nostealifdsv is the same asssv, these do nothing. Otherwise they all call some form of"sv_setsv". They may evaluate their arguments more than once.
The only differences are:
SvSetMagicSV andSvSetMagicSV_nosteal perform any required 'set' magic afterwards on the destination SV;SvSetSV andSvSetSV_nosteal do not.
SvSetSV_nostealSvSetMagicSV_nosteal call a non-destructive version ofsv_setsv.
void SvSetMagicSV(SV* dsv, SV* ssv)sv_setnvsv_setnv_mgThese copy a double into the given SV, upgrading first if necessary.
They differ only in thatsv_setnv_mg handles 'set' magic;sv_setnv does not.
void sv_setnv(SV * const sv, const NV num)sv_setpvsv_setpv_mgsv_setpvnsv_setpvn_freshsv_setpvn_mgsv_setpvssv_setpvs_mgThese copy a string into the SVsv, making sure it is"SvPOK_only".
In thepvs forms, the string must be a C literal string, enclosed in double quotes.
In thepvn forms, the first byte of the string is pointed to byptr, andlen indicates the number of bytes to be copied, potentially including embeddedNUL characters.
In the plainpv forms,ptr points to a NUL-terminated C string. That is, it points to the first byte of the string, and the copy proceeds up through the first encounteredNUL byte.
In the forms that take aptr argument, if it is NULL, the SV will become undefined.
The UTF-8 flag is not changed by these functions.
A terminating NUL byte is guaranteed in the result.
The_mg forms handle 'set' magic; the other forms skip all magic.
sv_setpvn_fresh is a cut-down alternative tosv_setpvn, intended ONLY to be used with a fresh sv that has been upgraded to a SVt_PV, SVt_PVIV, SVt_PVNV, or SVt_PVMG.
void sv_setpv (SV * const sv, const char * const ptr)void sv_setpv_mg (SV * const sv, const char * const ptr)void sv_setpvn (SV * const sv, const char * const ptr, const STRLEN len)void sv_setpvn_fresh(SV * const sv, const char * const ptr, const STRLEN len)void sv_setpvn_mg (SV * const sv, const char * const ptr, const STRLEN len)void sv_setpvs (SV* sv, "literal string")void sv_setpvs_mg (SV* sv, "literal string")sv_setpv_bufsizeSets the SV to be a string ofcur bytes length, with at leastlen bytes available. Ensures that there is a null byte atSvEND.
Returns a char * pointer to the SvPV buffer.
The caller must set the firstcur bytes ofsv before the first use of its contents. This means that ifcur is zero, the SV is immediately fully formed and ready to use, just like any other SV containing an empty string.
char * sv_setpv_bufsize(SV * const sv, const STRLEN cur, const STRLEN len)sv_setpvfsv_setpvf_mgsv_setpvf_mg_nocontextsv_setpvf_nocontextThese work like"sv_catpvf" but copy the text into the SV instead of appending it.
The differences between these are:
sv_setpvf_mg andsv_setpvf_mg_nocontext perform 'set' magic;sv_setpvf andsv_setpvf_nocontext skip all magic.
sv_setpvf_nocontext andsv_setpvf_mg_nocontext do not take a thread context (aTHX) parameter, so are used in situations where the caller doesn't already have the thread context.
The UTF-8 flag is not changed by these functions.
NOTE:sv_setpvf must be explicitly called asPerl_sv_setpvf with anaTHX_ parameter.
NOTE:sv_setpvf_mg must be explicitly called asPerl_sv_setpvf_mg with anaTHX_ parameter.
void Perl_sv_setpvf (pTHX_ SV * const sv, const char * const pat, ...)void Perl_sv_setpvf_mg (pTHX_ SV * const sv, const char * const pat, ...)void sv_setpvf_mg_nocontext(SV * const sv, const char * const pat, ...)void sv_setpvf_nocontext (SV * const sv, const char * const pat, ...)sv_setref_ivCopies an integer into a new SV, optionally blessing the SV. Therv argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname argument indicates the package for the blessing. Setclassname toNULL to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV * sv_setref_iv(SV * const rv, const char * const classname, const IV iv)sv_setref_nvCopies a double into a new SV, optionally blessing the SV. Therv argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname argument indicates the package for the blessing. Setclassname toNULL to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV * sv_setref_nv(SV * const rv, const char * const classname, const NV nv)sv_setref_pvCopies a pointer into a new SV, optionally blessing the SV. Therv argument will be upgraded to an RV. That RV will be modified to point to the new SV. If thepv argument isNULL, thenPL_sv_undef will be placed into the SV. Theclassname argument indicates the package for the blessing. Setclassname toNULL to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Do not use with other Perl types such as HV, AV, SV, CV, because those objects will become corrupted by the pointer copy process.
Note thatsv_setref_pvn copies the string while this copies the pointer.
SV * sv_setref_pv(SV * const rv, const char * const classname, void * const pv)sv_setref_pvnCopies a string into a new SV, optionally blessing the SV. The length of the string must be specified withn. Therv argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname argument indicates the package for the blessing. Setclassname toNULL to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Note thatsv_setref_pv copies the pointer while this copies the string.
SV * sv_setref_pvn(SV * const rv, const char * const classname, const char * const pv, const STRLEN n)sv_setref_pvsLikesv_setref_pvn, but takes a literal string instead of a string/length pair.
SV * sv_setref_pvs(SV *const rv, const char *const classname, "literal string")sv_setref_uvCopies an unsigned integer into a new SV, optionally blessing the SV. Therv argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname argument indicates the package for the blessing. Setclassname toNULL to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV * sv_setref_uv(SV * const rv, const char * const classname, const UV uv)sv_setrv_incsv_setrv_inc_mgAssv_setrv_noinc but increments the reference count ofref.
sv_setrv_inc_mg will invoke 'set' magic on the SV;sv_setrv_inc will not.
void sv_setrv_inc(SV * const sv, SV * const ref)sv_setrv_noincsv_setrv_noinc_mgCopies an SV pointer into the given SV as an SV reference, upgrading it if necessary. After this,SvRV(sv) is equal toref. This does not adjust the reference count ofref. The referenceref must not be NULL.
sv_setrv_noinc_mg will invoke 'set' magic on the SV;sv_setrv_noinc will not.
void sv_setrv_noinc(SV * const sv, SV * const ref)sv_setsvsv_setsv_flagssv_setsv_mgsv_setsv_nomgThese copy the contents of the source SVssv into the destination SVdsv.ssv may be destroyed if it is mortal, so don't use these functions if the source SV needs to be reused. Loosely speaking, they perform a copy-by-value, obliterating any previous content of the destination.
They differ only in that:
sv_setsv calls 'get' magic onssv, but skips 'set' magic ondsv.
sv_setsv_mg calls both 'get' magic onssv and 'set' magic ondsv.
sv_setsv_nomg skips all magic.
sv_setsv_flags has aflags parameter which you can use to specify any combination of magic handling, and also you can specifySV_NOSTEAL so that the buffers of temps will not be stolen.
You probably want to instead use one of the assortment of wrappers, such as"SvSetSV","SvSetSV_nosteal","SvSetMagicSV" and"SvSetMagicSV_nosteal".
sv_setsv_flags is the primary function for copying scalars, and most other copy-ish functions and macros use it underneath.
void sv_setsv (SV *dsv, SV *ssv)void sv_setsv_flags(SV *dsv, SV *ssv, const I32 flags)void sv_setsv_mg (SV * const dsv, SV * const ssv)void sv_setsv_nomg (SV *dsv, SV *ssv)sv_set_trueEquivalent tosv_setsv(sv, &PL_sv_yes), but may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is$sv = !0;.
Introduced in perl 5.35.11.
void sv_set_true(SV *sv)sv_set_undefEquivalent tosv_setsv(sv, &PL_sv_undef), but more efficient. Doesn't handle set magic.
The perl equivalent is$sv = undef;. Note that it doesn't free any string buffer, unlikeundef $sv.
Introduced in perl 5.25.12.
void sv_set_undef(SV *sv)sv_setuvsv_setuv_mgThese copy an unsigned integer into the given SV, upgrading first if necessary.
They differ only in thatsv_setuv_mg handles 'set' magic;sv_setuv does not.
void sv_setuv (SV * const sv, const UV num)void sv_setuv_mg(SV * const sv, const UV u)SvSHAREArranges forsv to be shared between threads if a suitable module has been loaded.
void SvSHARE(SV* sv)SvSHARED_HASHReturns the hash forsv created by"newSVpvn_share".
struct hek* SvSHARED_HASH(SV * sv)SvSTASHReturns the stash of the SV.
HV* SvSTASH(SV* sv)SvSTASH_setSet the value of the STASH pointer insv to val. See"SvIV_set".
void SvSTASH_set(SV* sv, HV* val)sv_streqA convenient shortcut for callingsv_streq_flags with theSV_GMAGIC flag. This function basically behaves like the Perl code$sv1 eq $sv2.
bool sv_streq(SV *sv1, SV *sv2)sv_streq_flagsReturns a boolean indicating whether the strings in the two SVs are identical. If the flags argument has theSV_GMAGIC bit set, it handles get-magic too. Will coerce its args to strings if necessary. TreatsNULL as undef. Correctly handles the UTF8 flag.
If flags does not have theSV_SKIP_OVERLOAD bit set, an attempt to useeq overloading will be made. If such overloading does not exist or the flag is set, then regular string comparison will be used instead.
bool sv_streq_flags(SV *sv1, SV *sv2, const U32 flags)SvTRUESvTRUE_NNSvTRUE_nomgSvTRUE_nomg_NNSvTRUExThese return a boolean indicating whether Perl would evaluate the SV as true or false. See"SvOK" for a defined/undefined test.
As of Perl 5.32, all are guaranteed to evaluatesv only once. Prior to that release, onlySvTRUEx guaranteed single evaluation; nowSvTRUEx is identical toSvTRUE.
SvTRUE_nomg andTRUE_nomg_NN do not perform 'get' magic; the others do unless the scalar is alreadySvPOK,SvIOK, orSvNOK (the public, not the private flags).
SvTRUE_NN is like"SvTRUE", butsv is assumed to be non-null (NN). If there is a possibility that it is NULL, use plainSvTRUE.
SvTRUE_nomg_NN is like"SvTRUE_nomg", butsv is assumed to be non-null (NN). If there is a possibility that it is NULL, use plainSvTRUE_nomg.
bool SvTRUE(SV *sv)SvUNLOCKReleases a mutual exclusion lock onsv if a suitable module has been loaded.
void SvUNLOCK(SV* sv)sv_unmagicRemoves all magic of typetype from an SV.
int sv_unmagic(SV * const sv, const int type)sv_unmagicextRemoves all magic of typetype with the specifiedvtbl from an SV.
int sv_unmagicext(SV * const sv, const int type, const MGVTBL *vtbl)sv_unrefUnsets the RV status of the SV, and decrements the reference count of whatever was being referenced by the RV. This can almost be thought of as a reversal ofnewSVrv. This issv_unref_flags with theflag being zero. See"SvROK_off".
void sv_unref(SV *sv)sv_unref_flagsUnsets the RV status of the SV, and decrements the reference count of whatever was being referenced by the RV. This can almost be thought of as a reversal ofnewSVrv. Thecflags argument can containSV_IMMEDIATE_UNREF to force the reference count to be decremented (otherwise the decrementing is conditional on the reference count being different from one or the reference being a readonly SV). See"SvROK_off".
void sv_unref_flags(SV * const ref, const U32 flags)SvUOKReturns a boolean indicating whether the SV contains an integer that must be interpreted as unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be flagged as eitherSvUOK orSvIOK.
bool SvUOK(SV* sv)SvUPGRADEUsed to upgrade an SV to a more complex form. Usessv_upgrade to perform the upgrade if necessary. See"svtype".
void SvUPGRADE(SV* sv, svtype type)sv_upgradeUpgrade an SV to a more complex form. Generally adds a new body type to the SV, then copies across as much information as possible from the old body. It croaks if the SV is already in a more complex form than requested. You generally want to use theSvUPGRADE macro wrapper, which checks the type before callingsv_upgrade, and hence does not croak. See also"svtype".
void sv_upgrade(SV * const sv, svtype new_type)sv_usepvnsv_usepvn_flagssv_usepvn_mgThese tell an SV to useptr for its string value. Normally SVs have their string stored inside the SV, but these tell the SV to use an external string instead.
ptr should point to memory that was allocated by"Newx". It must be the start of aNewx-ed block of memory, and not a pointer to the middle of it (beware ofOOK and copy-on-write), and not be from a non-Newx memory allocator likemalloc. The string length,len, must be supplied. By default this function will"Renew" (i.e. realloc, move) the memory pointed to byptr, so that the pointer should not be freed or used by the programmer after giving it tosv_usepvn, and neither should any pointers from "behind" that pointer (e.g.,ptr + 1) be used.
In thesv_usepvn_flags form, ifflags & SV_SMAGIC is true,SvSETMAGIC is called before returning. And ifflags & SV_HAS_TRAILING_NUL is true, thenptr[len] must beNUL, and the realloc will be skipped (i.e., the buffer is actually at least 1 byte longer thanlen, and already meets the requirements for storing inSvPVX).
sv_usepvn is merelysv_usepvn_flags withflags set to 0, so 'set' magic is skipped.
sv_usepvn_mg is merelysv_usepvn_flags withflags set toSV_SMAGIC, so 'set' magic is performed.
void sv_usepvn (SV *sv, char *ptr, STRLEN len)void sv_usepvn_flags(SV * const sv, char *ptr, const STRLEN len, const U32 flags)void sv_usepvn_mg (SV *sv, char *ptr, STRLEN len)sv_utf8_decodeIf the PV of the SV is an octet sequence in Perl's extended UTF-8 and contains a multiple-byte character, theSvUTF8 flag is turned on so that it looks like a character. If the PV contains only single-byte characters, theSvUTF8 flag stays off. Scans PV for validity and returns FALSE if the PV is invalid UTF-8.
bool sv_utf8_decode(SV * const sv)sv_utf8_downgradesv_utf8_downgrade_flagssv_utf8_downgrade_nomgThese attempt to convert the PV of an SV from characters to bytes. If the PV contains a character that cannot fit in a byte, this conversion will fail; in this case,FALSE is returned iffail_ok is true; otherwise they croak.
They are not a general purpose Unicode to byte encoding interface: use theEncode extension for that.
They differ only in that:
sv_utf8_downgrade processes 'get' magic onsv.
sv_utf8_downgrade_nomg does not.
sv_utf8_downgrade_flags has an additionalflags parameter in which you can specifySV_GMAGIC to process 'get' magic, or leave it cleared to not process 'get' magic.
bool sv_utf8_downgrade (SV * const sv, const bool fail_ok)bool sv_utf8_downgrade_flags(SV * const sv, const bool fail_ok, const U32 flags)bool sv_utf8_downgrade_nomg (SV * const sv, const bool fail_ok)sv_utf8_encodeConverts the PV of an SV to UTF-8, but then turns theSvUTF8 flag off so that it looks like octets again.
void sv_utf8_encode(SV * const sv)SvUTF8_offUnsets the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_off(SV *sv)SvUTF8_onTurn on the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_on(SV *sv)sv_utf8_upgradesv_utf8_upgrade_flagssv_utf8_upgrade_flags_growsv_utf8_upgrade_nomgThese convert the PV of an SV to its UTF-8-encoded form. The SV is forced to string form if it is not already. They always set theSvUTF8 flag to avoid future validity checks even if the whole string is the same in UTF-8 as not. They return the number of bytes in the converted string
The forms differ in just two ways. The main difference is whether or not they perform 'get magic' onsv.sv_utf8_upgrade_nomg skips 'get magic';sv_utf8_upgrade performs it; andsv_utf8_upgrade_flags andsv_utf8_upgrade_flags_grow either perform it (if theSV_GMAGIC bit is set inflags) or don't (if that bit is cleared).
The other difference is thatsv_utf8_upgrade_flags_grow has an additional parameter,extra, which allows the caller to specify an amount of space to be reserved as spare beyond what is needed for the actual conversion. This is used when the caller knows it will soon be needing yet more space, and it is more efficient to request space from the system in a single call. This form is otherwise identical tosv_utf8_upgrade_flags.
These are not a general purpose byte encoding to Unicode interface: use the Encode extension for that.
TheSV_FORCE_UTF8_UPGRADE flag is now ignored.
STRLEN sv_utf8_upgrade (SV *sv)STRLEN sv_utf8_upgrade_flags (SV * const sv, const I32 flags)STRLEN sv_utf8_upgrade_flags_grow(SV * const sv, const I32 flags, STRLEN extra)STRLEN sv_utf8_upgrade_nomg (SV *sv)SvUTF8Returns a U32 value indicating the UTF-8 status of an SV. If things are set-up properly, this indicates whether or not the SV contains UTF-8 encoded data. You should use thisafter a call to"SvPV" or one of its variants, in case any call to string overloading updates the internal flag.
If you want to take into account thebytes pragma, use"DO_UTF8" instead.
U32 SvUTF8(SV* sv)SvUVSvUV_nomgSvUVxThese each coerce the given SV to UV and return it. The returned value in many circumstances will get stored insv's UV slot, but not in all cases. (Use"sv_setuv" to make sure it does).
As of 5.37.1, all are guaranteed to evaluatesv only once.
SvUVx is now identical toSvUV, but prior to 5.37.1, it was the only form guaranteed to evaluatesv only once.
UV SvUV(SV *sv)sv_2uv_flagsReturn the unsigned integer value of an SV, doing any necessary string conversion. Ifflags has theSV_GMAGIC bit set, does anmg_get() first. Normally used via theSvUV(sv) andSvUVx(sv) macros.
UV sv_2uv_flags(SV * const sv, const I32 flags)SvUV_setSet the value of the UV pointer insv to val. See"SvIV_set".
void SvUV_set(SV* sv, UV val)SvUVXReturns the raw value in the SV's UV slot, without checks or conversions. Only use when you are sureSvIOK is true. See also"SvUV".
UV SvUVX(SV* sv)SvUVXxDEPRECATED! It is planned to removeSvUVXx from a future release of Perl. Do not use it for new code; remove it from existing code.
This is an unnecessary synonym for"SvUVX"
UV SvUVXx(SV* sv)sv_vcatpvfsv_vcatpvf_mgThese process their arguments likesv_vcatpvfn called with a non-null C-style variable argument list, and append the formatted output tosv.
They differ only in thatsv_vcatpvf_mg performs 'set' magic;sv_vcatpvf skips 'set' magic.
Both perform 'get' magic.
They are usually accessed via their frontends"sv_catpvf" and"sv_catpvf_mg".
void sv_vcatpvf(SV * const sv, const char * const pat, va_list * const args)sv_vcatpvfnsv_vcatpvfn_flagsThese process their arguments likevsprintf(3) and append the formatted output to an SV. They use an array of SVs if the C-style variable argument list is missing (NULL). Argument reordering (using format specifiers like%2$d or%*2$d) is supported only when using an array of SVs; using a C-styleva_list argument list with a format string that uses argument reordering will yield an exception.
When running with taint checks enabled, they indicate viamaybe_tainted if results are untrustworthy (often due to the use of locales).
They assume thatpat has the same utf8-ness assv. It's the caller's responsibility to ensure that this is so.
They differ in thatsv_vcatpvfn_flags has aflags parameter in which you can set or clear theSV_GMAGIC and/orSV_SMAGIC flags, to specify which magic to handle or not handle; whereas plainsv_vcatpvfn always specifies both 'get' and 'set' magic.
They are usually used via one of the frontends"sv_vcatpvf" and"sv_vcatpvf_mg".
void sv_vcatpvfn (SV * const sv, const char * const pat, const STRLEN patlen, va_list * const args, SV ** const svargs, const Size_t sv_count, bool * const maybe_tainted)void sv_vcatpvfn_flags(SV * const sv, const char * const pat, const STRLEN patlen, va_list * const args, SV ** const svargs, const Size_t sv_count, bool * const maybe_tainted, const U32 flags)SvVOKReturns a boolean indicating whether the SV contains a v-string.
bool SvVOK(SV* sv)sv_vsetpvfsv_vsetpvf_mgThese work like"sv_vcatpvf" but copy the text into the SV instead of appending it.
They differ only in thatsv_vsetpvf_mg performs 'set' magic;sv_vsetpvf skips all magic.
They are usually used via their frontends,"sv_setpvf" and"sv_setpvf_mg".
The UTF-8 flag is not changed by these functions.
void sv_vsetpvf(SV * const sv, const char * const pat, va_list * const args)sv_vsetpvfnWorks likesv_vcatpvfn but copies the text into the SV instead of appending it.
The UTF-8 flag is not changed by this function.
Usually used via one of its frontends"sv_vsetpvf" and"sv_vsetpvf_mg".
void sv_vsetpvfn(SV * const sv, const char * const pat, const STRLEN patlen, va_list * const args, SV ** const svargs, const Size_t sv_count, bool * const maybe_tainted)SvVSTRING_mgReturns the vstring magic, or NULL if none
MAGIC* SvVSTRING_mg(SV * sv)vnewSVpvfLike"newSVpvf" but the arguments are an encapsulated argument list.
SV * vnewSVpvf(const char * const pat, va_list * const args)SvTAINTTaints an SV if tainting is enabled, and if some input to the current expression is tainted--usually a variable, but possibly also implicit inputs such as locale settings.SvTAINT propagates that taintedness to the outputs of an expression in a pessimistic fashion; i.e., without paying attention to precisely which outputs are influenced by which inputs.
void SvTAINT(SV* sv)SvTAINTEDChecks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.
bool SvTAINTED(SV* sv)SvTAINTED_offUntaints an SV. Bevery careful with this routine, as it short-circuits some of Perl's fundamental security features. XS module authors should not use this function unless they fully understand all the implications of unconditionally untainting the value. Untainting should be done in the standard perl fashion, via a carefully crafted regexp, rather than directly untainting variables.
void SvTAINTED_off(SV* sv)SvTAINTED_onMarks an SV as tainted if tainting is enabled.
void SvTAINTED_on(SV* sv)ASCTIME_R_PROTOThis symbol encodes the prototype ofasctime_r. It is zero ifd_asctime_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_asctime_r is defined.
CTIME_R_PROTOThis symbol encodes the prototype ofctime_r. It is zero ifd_ctime_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_ctime_r is defined.
GMTIME_MAXThis symbol contains the maximum value for thetime_t offset that the system function gmtime () accepts, and defaults to 0
GMTIME_MINThis symbol contains the minimum value for thetime_t offset that the system function gmtime () accepts, and defaults to 0
GMTIME_R_PROTOThis symbol encodes the prototype ofgmtime_r. It is zero ifd_gmtime_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_gmtime_r is defined.
HAS_ASCTIME_RThis symbol, if defined, indicates that theasctime_r routine is available to asctime re-entrantly.
HAS_ASCTIME64This symbol, if defined, indicates that theasctime64 () routine is available to do the 64bit variant of asctime ()
HAS_CTIME_RThis symbol, if defined, indicates that thectime_r routine is available to ctime re-entrantly.
HAS_CTIME64This symbol, if defined, indicates that thectime64 () routine is available to do the 64bit variant of ctime ()
HAS_DIFFTIMEThis symbol, if defined, indicates that thedifftime routine is available.
HAS_DIFFTIME64This symbol, if defined, indicates that thedifftime64 () routine is available to do the 64bit variant of difftime ()
HAS_FUTIMESThis symbol, if defined, indicates that thefutimes routine is available to change file descriptor time stamps withstruct timevals.
HAS_GETITIMERThis symbol, if defined, indicates that thegetitimer routine is available to return interval timers.
HAS_GETTIMEOFDAYThis symbol, if defined, indicates that thegettimeofday() system call is available for a sub-second accuracy clock. Usually, the filesys/resource.h needs to be included (see"I_SYS_RESOURCE"). The type "Timeval" should be used to refer to "struct timeval".
HAS_GMTIME_RThis symbol, if defined, indicates that thegmtime_r routine is available to gmtime re-entrantly.
HAS_GMTIME64This symbol, if defined, indicates that thegmtime64 () routine is available to do the 64bit variant of gmtime ()
HAS_LOCALTIME_RThis symbol, if defined, indicates that thelocaltime_r routine is available to localtime re-entrantly.
HAS_LOCALTIME64This symbol, if defined, indicates that thelocaltime64 () routine is available to do the 64bit variant of localtime ()
HAS_MKTIMEThis symbol, if defined, indicates that themktime routine is available.
HAS_MKTIME64This symbol, if defined, indicates that themktime64 () routine is available to do the 64bit variant of mktime ()
HAS_NANOSLEEPThis symbol, if defined, indicates that thenanosleep system call is available to sleep with 1E-9 sec accuracy.
HAS_SETITIMERThis symbol, if defined, indicates that thesetitimer routine is available to set interval timers.
HAS_STRFTIMEThis symbol, if defined, indicates that thestrftime routine is available to do time formatting.
HAS_TIMEThis symbol, if defined, indicates that thetime() routine exists.
HAS_TIMEGMThis symbol, if defined, indicates that thetimegm routine is available to do the opposite of gmtime ()
HAS_TIMESThis symbol, if defined, indicates that thetimes() routine exists. Note that this became obsolete on some systems (SUNOS), which now usegetrusage(). It may be necessary to includesys/times.h.
HAS_TM_TM_GMTOFFThis symbol, if defined, indicates to the C program that thestruct tm has atm_gmtoff field.
HAS_TM_TM_ZONEThis symbol, if defined, indicates to the C program that thestruct tm has atm_zone field.
HAS_TZNAMEThis symbol, if defined, indicates that thetzname[] array is available to access timezone names.
HAS_USLEEPThis symbol, if defined, indicates that theusleep routine is available to let the process sleep on a sub-second accuracy.
HAS_USLEEP_PROTOThis symbol, if defined, indicates that the system provides a prototype for theusleep() function. Otherwise, it is up to the program to supply one. A good guess is
extern int usleep(useconds_t);I_TIMEThis symbol is always defined, and indicates to the C program that it should includetime.h.
#ifdef I_TIME #include <time.h>#endifI_UTIMEThis symbol, if defined, indicates to the C program that it should includeutime.h.
#ifdef I_UTIME #include <utime.h>#endifLOCALTIME_MAXThis symbol contains the maximum value for thetime_t offset that the system function localtime () accepts, and defaults to 0
LOCALTIME_MINThis symbol contains the minimum value for thetime_t offset that the system function localtime () accepts, and defaults to 0
LOCALTIME_R_NEEDS_TZSETMany libc'slocaltime_r implementations do not call tzset, making them differ fromlocaltime(), and making timezone changes using $ENV{TZ} without explicitly calling tzset impossible. This symbol makes us call tzset beforelocaltime_r
LOCALTIME_R_PROTOThis symbol encodes the prototype oflocaltime_r. It is zero ifd_localtime_r is undef, and one of theREENTRANT_PROTO_T_ABC macros ofreentr.h ifd_localtime_r is defined.
L_R_TZSETIflocaltime_r() needs tzset, it is defined in this define
mini_mktimenormalisestruct tm values without the localtime() semantics (and overhead) of mktime().
void mini_mktime(struct tm *ptm)sv_strftime_tmsv_strftime_intsmy_strftimeThese implement the libc strftime(), but with a different API so that the return value is a pointer to the formatted result (which MUST be arranged to be FREED BY THE CALLER). This allows these functions to increase the buffer size as needed, so that the caller doesn't have to worry about that.
On failure, they return NULL, and seterrno toEINVAL.
sv_strftime_tm andsv_strftime_ints are preferred, as they transparently handle the UTF-8ness of the current locale, the inputfmt, and the returned result. Only if the currentLC_TIME locale is a UTF-8 one (anduse bytes is not in effect) will the result be marked as UTF-8. These differ only in the form of their inputs.sv_strftime_tm takes a filled-instruct tm parameter.sv_strftime_ints takes a bunch of integer parameters that together completely define a given time.
my_strftime is kept for backwards compatibility. Knowing if its result should be considered UTF-8 or not requires significant extra logic.
Note thatyday andwday effectively are ignored bysv_strftime_ints andmy_strftime, as mini_mktime() overwrites them
Also note that all three functions are always executed in the underlyingLC_TIME locale of the program, giving results based on that locale.
SV * sv_strftime_tm (SV *fmt, const struct tm *mytm)SV * sv_strftime_ints(SV *fmt, int sec, int min, int hour, int mday, int mon, int year, int wday, int yday, int isdst)char * my_strftime (const char *fmt, int sec, int min, int hour, int mday, int mon, int year, int wday, int yday, int isdst)switch_to_global_localeThis function copies the locale state of the calling thread into the program's global locale, and converts the thread to use that global locale.
It is intended so that Perl can safely be used with C libraries that access the global locale and which can't be converted to not access it. Effectively, this means libraries that callsetlocale(3) on non-Windows systems. (For portability, it is a good idea to use it on Windows as well.)
A downside of using it is that it disables the services that Perl provides to hide locale gotchas from your code. The service you most likely will miss regards the radix character (decimal point) in floating point numbers. Code executed after this function is called can no longer just assume that this character is correct for the current circumstances.
To return to Perl control, and restart the gotcha prevention services, call"sync_locale". Behavior is undefined for any pure Perl code that executes while the switch is in effect.
The global locale and the per-thread locales are independent. As long as just one thread converts to the global locale, everything works smoothly. But if more than one does, they can easily interfere with each other, and races are likely. On Windows systems prior to Visual Studio 15 (at which point Microsoft fixed a bug), races can occur (even if only one thread has been converted to the global locale), but only if you use the following operations:
CRNCYSTR andTHOUSEPCRNCYSTR andTHOUSEPThe first item is not fixable (except by upgrading to a later Visual Studio release), but it would be possible to work around the latter two items by having Perl change its algorithm for calculating these to use Windows API functions (likelyGetNumberFormat andGetCurrencyFormat); patches welcome.
XS code should never call plainsetlocale, but should instead be converted to either callPerl_setlocale (which is a drop-in for the systemsetlocale) or use the methods given inperlcall to callPOSIX::setlocale. Either one will transparently properly handle all cases of single- vs multi-thread, POSIX 2008-supported or not.
void switch_to_global_locale()sync_localeThis function copies the state of the program global locale into the calling thread, and converts that thread to using per-thread locales, if it wasn't already, and the platform supports them. The LC_NUMERIC locale is toggled into the standard state (using the C locale's conventions), if not within the lexical scope ofuse locale.
Perl will now consider itself to have control of the locale.
Since unthreaded perls have only a global locale, this function is a no-op without threads.
This function is intended for use with C libraries that do locale manipulation. It allows Perl to accommodate the use of them. Call this function before transferring back to Perl space so that it knows what state the C code has left things in.
XS code should not manipulate the locale on its own. Instead,Perl_setlocale can be used at any time to query or change the locale (though changing the locale is antisocial and dangerous on multi-threaded systems that don't have multi-thread safe locale operations. (See"Multi-threaded operation" in perllocale).
Using the libcsetlocale(3) function should be avoided. Nevertheless, certain non-Perl libraries called from XS, do call it, and their behavior may not be able to be changed. This function, along with"switch_to_global_locale", can be used to get seamless behavior in these circumstances, as long as only one thread is involved.
If the library has an option to turn off its locale manipulation, doing that is preferable to using this mechanism.Gtk is such a library.
The return value is a boolean: TRUE if the global locale at the time of call was in effect for the caller; and FALSE if a per-thread locale was in effect.
bool sync_locale()DB_Hash_tThis symbol contains the type of the prefix structure element in thedb.h header file. In older versions of DB, it was int, while in newer ones it issize_t.
DB_Prefix_tThis symbol contains the type of the prefix structure element in thedb.h header file. In older versions of DB, it was int, while in newer ones it isu_int32_t.
Direntry_tThis symbol is set to 'struct direct' or 'struct dirent' depending on whether dirent is available or not. You should use this pseudo type to portably declare your directory entries.
Fpos_tThis symbol holds the type used to declare file positions in libc. It can befpos_t, long, uint, etc... It may be necessary to includesys/types.h to get any typedef'ed information.
Free_tThis variable contains the return type offree(). It is usually void, but occasionally int.
Gid_tThis symbol holds the return type ofgetgid() and the type of argument tosetrgid() and related functions. Typically, it is the type of group ids in the kernel. It can be int, ushort,gid_t, etc... It may be necessary to includesys/types.h to get any typedef'ed information.
Gid_t_fThis symbol defines the format string used for printing aGid_t.
Gid_t_signThis symbol holds the signedness of aGid_t. 1 for unsigned, -1 for signed.
Gid_t_sizeThis symbol holds the size of aGid_t in bytes.
Groups_tThis symbol holds the type used for the second argument togetgroups() andsetgroups(). Usually, this is the same as gidtype (gid_t) , but sometimes it isn't. It can be int, ushort,gid_t, etc... It may be necessary to includesys/types.h to get any typedef'ed information. This is only required if you havegetgroups() orsetgroups()..
Malloc_tThis symbol is the type of pointer returned by malloc and realloc.
Mmap_tThis symbol holds the return type of themmap() system call (and simultaneously the type of the first argument). Usually set to 'void *' or 'caddr_t'.
Mode_tThis symbol holds the type used to declare file modes for systems calls. It is usuallymode_t, but may be int or unsigned short. It may be necessary to includesys/types.h to get any typedef'ed information.
Netdb_hlen_tThis symbol holds the type used for the 2nd argument togethostbyaddr().
Netdb_host_tThis symbol holds the type used for the 1st argument togethostbyaddr().
Netdb_name_tThis symbol holds the type used for the argument togethostbyname().
Netdb_net_tThis symbol holds the type used for the 1st argument togetnetbyaddr().
Off_tThis symbol holds the type used to declare offsets in the kernel. It can be int, long,off_t, etc... It may be necessary to includesys/types.h to get any typedef'ed information.
Off_t_sizeThis symbol holds the number of bytes used by theOff_t.
Pid_tThis symbol holds the type used to declare process ids in the kernel. It can be int, uint,pid_t, etc... It may be necessary to includesys/types.h to get any typedef'ed information.
Rand_seed_tThis symbol defines the type of the argument of the random seed function.
Select_fd_set_tThis symbol holds the type used for the 2nd, 3rd, and 4th arguments to select. Usually, this is 'fd_set *', ifHAS_FD_SET is defined, and 'int *' otherwise. This is only useful if you haveselect(), of course.
Shmat_tThis symbol holds the return type of theshmat() system call. Usually set to 'void *' or 'char *'.
Signal_tThis symbol's value is either "void" or "int", corresponding to the appropriate return type of a signal handler. Thus, you can declare a signal handler using "Signal_t (*handler)()", and define the handler using "Signal_thandler(sig)".
Size_tThis symbol holds the type used to declare length parameters for string functions. It is usuallysize_t, but may be unsigned long, int, etc. It may be necessary to includesys/types.h to get any typedef'ed information.
Size_t_sizeThis symbol holds the size of aSize_t in bytes.
Sock_size_tThis symbol holds the type used for the size argument of various socket calls (just the base type, not the pointer-to).
SSize_tThis symbol holds the type used by functions that return a count of bytes or an error condition. It must be a signed type. It is usuallyssize_t, but may be long or int, etc. It may be necessary to includesys/types.h orunistd.h to get any typedef'ed information. We will pick a type such thatsizeof(SSize_t) ==sizeof(Size_t).
Time_tThis symbol holds the type returned bytime(). It can be long, ortime_t onBSD sites (in which casesys/types.h should be included).
Uid_tThis symbol holds the type used to declare user ids in the kernel. It can be int, ushort,uid_t, etc... It may be necessary to includesys/types.h to get any typedef'ed information.
Uid_t_fThis symbol defines the format string used for printing aUid_t.
Uid_t_signThis symbol holds the signedness of aUid_t. 1 for unsigned, -1 for signed.
Uid_t_sizeThis symbol holds the size of aUid_t in bytes.
"Unicode Support" in perlguts has an introduction to this API.
See also"Character classification","Character case changing", and"String Handling". Various functions outside this section also work specially with Unicode. Search for the string "utf8" in this document.
BOM_UTF8This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode BYTE ORDER MARK (U+FEFF) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms.sizeof(BOM_UTF8) - 1 can be used to get its length in bytes.
bytes_cmp_utf8Compares the sequence of characters (stored as octets) inb,blen with the sequence of characters (stored as UTF-8) inu,ulen. Returns 0 if they are equal, -1 or -2 if the first string is less than the second string, +1 or +2 if the first string is greater than the second string.
-1 or +1 is returned if the shorter string was identical to the start of the longer string. -2 or +2 is returned if there was a difference between characters within the strings.
int bytes_cmp_utf8(const U8 *b, STRLEN blen, const U8 *u, STRLEN ulen)bytes_from_utf8NOTE:bytes_from_utf8 isexperimental and may change or be removed without notice.
Converts a potentially UTF-8 encoded strings of length*lenp into native byte encoding. On input, the boolean*is_utf8p gives whether or nots is actually encoded in UTF-8.
Unlike"utf8_to_bytes" but like"bytes_to_utf8", this is non-destructive of the input string.
Do nothing if*is_utf8p is 0, or if there are code points in the string not expressible in native byte encoding. In these cases,*is_utf8p and*lenp are unchanged, and the return value is the originals.
Otherwise,*is_utf8p is set to 0, and the return value is a pointer to a newly created string containing a downgraded copy ofs, and whose length is returned in*lenp, updated. The new string isNUL-terminated. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of*lenp before the call, and subtracting the after-call value of*lenp from it.
U8 * bytes_from_utf8(const U8 *s, STRLEN *lenp, bool *is_utf8p)bytes_to_utf8NOTE:bytes_to_utf8 isexperimental and may change or be removed without notice.
Converts a strings of length*lenp bytes from the native encoding into UTF-8. Returns a pointer to the newly-created string, and sets*lenp to reflect the new length in bytes. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of*lenp before the call, and subtracting it from the after-call value of*lenp.
ANUL character will be written after the end of the string.
If you want to convert to UTF-8 from encodings other than the native (Latin1 or EBCDIC), see"sv_recode_to_utf8"().
U8 * bytes_to_utf8(const U8 *s, STRLEN *lenp)DO_UTF8Returns a bool giving whether or not the PV insv is to be treated as being encoded in UTF-8.
You should use thisafter a call toSvPV() or one of its variants, in case any call to string overloading updates the internal UTF-8 encoding flag.
bool DO_UTF8(SV* sv)foldEQ_utf8Returns true if the leading portions of the stringss1 ands2 (either or both of which may be in UTF-8) are the same case-insensitively; false otherwise. How far into the strings to compare is determined by other input parameters.
Ifu1 is true, the strings1 is assumed to be in UTF-8-encoded Unicode; otherwise it is assumed to be in native 8-bit encoding. Correspondingly foru2 with respect tos2.
If the byte lengthl1 is non-zero, it says how far intos1 to check for fold equality. In other words,s1+l1 will be used as a goal to reach. The scan will not be considered to be a match unless the goal is reached, and scanning won't continue past that goal. Correspondingly forl2 with respect tos2.
Ifpe1 is non-NULL and the pointer it points to is notNULL, that pointer is considered an end pointer to the position 1 byte past the maximum point ins1 beyond which scanning will not continue under any circumstances. (This routine assumes that UTF-8 encoded input strings are not malformed; malformed input can cause it to read pastpe1). This means that if bothl1 andpe1 are specified, andpe1 is less thans1+l1, the match will never be successful because it can never get as far as its goal (and in fact is asserted against). Correspondingly forpe2 with respect tos2.
At least one ofs1 ands2 must have a goal (at least one ofl1 andl2 must be non-zero), and if both do, both have to be reached for a successful match. Also, if the fold of a character is multiple characters, all of them must be matched (see tr21 reference below for 'folding').
Upon a successful match, ifpe1 is non-NULL, it will be set to point to the beginning of thenext character ofs1 beyond what was matched. Correspondingly forpe2 ands2.
For case-insensitiveness, the "casefolding" of Unicode is used instead of upper/lowercasing both the characters, seehttps://www.unicode.org/reports/tr21/ (Case Mappings).
I32 foldEQ_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)is_ascii_stringThis is a misleadingly-named synonym for"is_utf8_invariant_string". On ASCII-ish platforms, the name isn't misleading: the ASCII-range characters are exactly the UTF-8 invariants. But EBCDIC machines have more invariants than just the ASCII characters, sois_utf8_invariant_string is preferred.
bool is_ascii_string(const U8 * const s, STRLEN len)isC9_STRICT_UTF8_CHAREvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents some Unicode non-surrogate code point; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF. This differs from"isSTRICT_UTF8_CHAR" only in that it accepts non-character code points. This corresponds toUnicode Corrigendum #9. which said that non-character code points are merely discouraged rather than completely forbidden in open interchange. See"Noncharacter code points" in perlunicode.
Use"isUTF8_CHAR" to check for Perl's extended UTF-8; and"isUTF8_CHAR_flags" for a more customized definition.
Use"is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen" to check entire strings.
Size_t isC9_STRICT_UTF8_CHAR(const U8 * const s0, const U8 * const e)is_c9strict_utf8_stringReturns TRUE if the firstlen bytes of strings form a valid UTF-8-encoded string that conforms toUnicode Corrigendum #9; otherwise it returns FALSE. Iflen is 0, it will be calculated usingstrlen(s) (which means if you use this option, thats can't have embeddedNUL characters and has to have a terminatingNUL byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
This function returns FALSE for strings containing any code points above the Unicode max of 0x10FFFF or surrogate code points, but accepts non-character code points perCorrigendum #9.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string","is_utf8_string_flags","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
bool is_c9strict_utf8_string(const U8 *s, STRLEN len)is_c9strict_utf8_string_locLike"is_c9strict_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer.
See also"is_c9strict_utf8_string_loclen".
bool is_c9strict_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)is_c9strict_utf8_string_loclenLike"is_c9strict_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_c9strict_utf8_string_loc".
bool is_c9strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)is_invariant_stringThis is a somewhat misleadingly-named synonym for"is_utf8_invariant_string".is_utf8_invariant_string is preferred, as it indicates under what conditions the string is invariant.
bool is_invariant_string(const U8 * const s, STRLEN len)isSTRICT_UTF8_CHAREvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents some Unicode code point completely acceptable for open interchange between all applications; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF, and must not be a surrogate nor a non-character code point. Thus this excludes any code point from Perl's extended UTF-8.
This is used to efficiently decide if the next few bytes ins is legal Unicode-acceptable UTF-8 for a single character.
Use"isC9_STRICT_UTF8_CHAR" to use theUnicode Corrigendum #9 definition of allowable code points;"isUTF8_CHAR" to check for Perl's extended UTF-8; and"isUTF8_CHAR_flags" for a more customized definition.
Use"is_strict_utf8_string","is_strict_utf8_string_loc", and"is_strict_utf8_string_loclen" to check entire strings.
Size_t isSTRICT_UTF8_CHAR(const U8 * const s0, const U8 * const e)is_strict_utf8_stringReturns TRUE if the firstlen bytes of strings form a valid UTF-8-encoded string that is fully interchangeable by any application using Unicode rules; otherwise it returns FALSE. Iflen is 0, it will be calculated usingstrlen(s) (which means if you use this option, thats can't have embeddedNUL characters and has to have a terminatingNUL byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
This function returns FALSE for strings containing any code points above the Unicode max of 0x10FFFF, surrogate code points, or non-character code points.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string","is_utf8_string_flags","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
bool is_strict_utf8_string(const U8 *s, STRLEN len)is_strict_utf8_string_locLike"is_strict_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer.
See also"is_strict_utf8_string_loclen".
bool is_strict_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)is_strict_utf8_string_loclenLike"is_strict_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_strict_utf8_string_loc".
bool is_strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)isUTF8_CHAREvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8, as extended by Perl, that represents some code point; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
The code point can be any that will fit in an IV on this machine, using Perl's extension to official UTF-8 to represent those higher than the Unicode maximum of 0x10FFFF. That means that this macro is used to efficiently decide if the next few bytes ins is legal UTF-8 for a single character.
Use"isSTRICT_UTF8_CHAR" to restrict the acceptable code points to those defined by Unicode to be fully interchangeable across applications;"isC9_STRICT_UTF8_CHAR" to use theUnicode Corrigendum #9 definition of allowable code points; and"isUTF8_CHAR_flags" for a more customized definition.
Use"is_utf8_string","is_utf8_string_loc", and"is_utf8_string_loclen" to check entire strings.
Note also that a UTF-8 "invariant" character (i.e. ASCII on non-EBCDIC machines) is a valid UTF-8 character.
Size_t isUTF8_CHAR(const U8 * const s0, const U8 * const e)is_utf8_char_bufThis is identical to the macro"isUTF8_CHAR" in perlapi.
STRLEN is_utf8_char_buf(const U8 *buf, const U8 *buf_end)isUTF8_CHAR_flagsEvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8, as extended by Perl, that represents some code point, subject to the restrictions given byflags; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
Ifflags is 0, this gives the same results as"isUTF8_CHAR"; ifflags isUTF8_DISALLOW_ILLEGAL_INTERCHANGE, this gives the same results as"isSTRICT_UTF8_CHAR"; and ifflags isUTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE, this gives the same results as"isC9_STRICT_UTF8_CHAR". Otherwiseflags may be any combination of theUTF8_DISALLOW_foo flags understood by"utf8n_to_uvchr", with the same meanings.
The three alternative macros are for the most commonly needed validations; they are likely to run somewhat faster than this more general one, as they can be inlined into your code.
Use"is_utf8_string_flags","is_utf8_string_loc_flags", and"is_utf8_string_loclen_flags" to check entire strings.
Size_t isUTF8_CHAR_flags(const U8 * const s0, const U8 * const e, const U32 flags)is_utf8_fixed_width_buf_flagsReturns TRUE if the fixed-width buffer starting ats with lengthlen is entirely valid UTF-8, subject to the restrictions given byflags; otherwise it returns FALSE.
Ifflags is 0, any well-formed UTF-8, as extended by Perl, is accepted without restriction. If the final few bytes of the buffer do not form a complete code point, this will return TRUE anyway, provided that"is_utf8_valid_partial_char_flags" returns TRUE for them.
Ifflags in non-zero, it can be any combination of theUTF8_DISALLOW_foo flags accepted by"utf8n_to_uvchr", and with the same meanings.
This function differs from"is_utf8_string_flags" only in that the latter returns FALSE if the final few bytes of the string don't form a complete code point.
bool is_utf8_fixed_width_buf_flags(const U8 * const s, STRLEN len, const U32 flags)is_utf8_fixed_width_buf_loc_flagsLike"is_utf8_fixed_width_buf_flags" but stores the location of the failure in theep pointer. If the function returns TRUE,*ep will point to the beginning of any partial character at the end of the buffer; if there is no partial character*ep will contains+len.
See also"is_utf8_fixed_width_buf_loclen_flags".
bool is_utf8_fixed_width_buf_loc_flags(const U8 * const s, STRLEN len, const U8 **ep, const U32 flags)is_utf8_fixed_width_buf_loclen_flagsLike"is_utf8_fixed_width_buf_loc_flags" but stores the number of complete, valid characters found in theel pointer.
bool is_utf8_fixed_width_buf_loclen_flags(const U8 * const s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)is_utf8_invariant_stringReturns TRUE if the firstlen bytes of the strings are the same regardless of the UTF-8 encoding of the string (or UTF-EBCDIC encoding on EBCDIC machines); otherwise it returns FALSE. That is, it returns TRUE if they are UTF-8 invariant. On ASCII-ish machines, all the ASCII characters and only the ASCII characters fit this definition. On EBCDIC machines, the ASCII-range characters are invariant, but so also are the C1 controls.
Iflen is 0, it will be calculated usingstrlen(s), (which means if you use this option, thats can't have embeddedNUL characters and has to have a terminatingNUL byte).
See also"is_utf8_string","is_utf8_string_flags","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
bool is_utf8_invariant_string(const U8 * const s, STRLEN len)is_utf8_invariant_string_locLike"is_utf8_invariant_string" but upon failure, stores the location of the first UTF-8 variant character in theep pointer; if all characters are UTF-8 invariant, this function does not change the contents of*ep.
bool is_utf8_invariant_string_loc(const U8 * const s, STRLEN len, const U8 **ep)is_utf8_stringReturns TRUE if the firstlen bytes of strings form a valid Perl-extended-UTF-8 string; returns FALSE otherwise. Iflen is 0, it will be calculated usingstrlen(s) (which means if you use this option, thats can't have embeddedNUL characters and has to have a terminatingNUL byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
This function considers Perl's extended UTF-8 to be valid. That means that code points above Unicode, surrogates, and non-character code points are considered valid by this function. Use"is_strict_utf8_string","is_c9strict_utf8_string", or"is_utf8_string_flags" to restrict what code points are considered valid.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string_loc","is_utf8_string_loclen","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags",
bool is_utf8_string(const U8 *s, STRLEN len)is_utf8_string_flagsReturns TRUE if the firstlen bytes of strings form a valid UTF-8 string, subject to the restrictions imposed byflags; returns FALSE otherwise. Iflen is 0, it will be calculated usingstrlen(s) (which means if you use this option, thats can't have embeddedNUL characters and has to have a terminatingNUL byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
Ifflags is 0, this gives the same results as"is_utf8_string"; ifflags isUTF8_DISALLOW_ILLEGAL_INTERCHANGE, this gives the same results as"is_strict_utf8_string"; and ifflags isUTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE, this gives the same results as"is_c9strict_utf8_string". Otherwiseflags may be any combination of theUTF8_DISALLOW_foo flags understood by"utf8n_to_uvchr", with the same meanings.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
bool is_utf8_string_flags(const U8 *s, STRLEN len, const U32 flags)is_utf8_string_locLike"is_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer.
See also"is_utf8_string_loclen".
bool is_utf8_string_loc(const U8 *s, const STRLEN len, const U8 **ep)is_utf8_string_loc_flagsLike"is_utf8_string_flags" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer.
See also"is_utf8_string_loclen_flags".
bool is_utf8_string_loc_flags(const U8 *s, STRLEN len, const U8 **ep, const U32 flags)is_utf8_string_loclenLike"is_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_utf8_string_loc".
bool is_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)is_utf8_string_loclen_flagsLike"is_utf8_string_flags" but stores the location of the failure (in the case of "utf8ness failure") or the locations+len (in the case of "utf8ness success") in theep pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_utf8_string_loc_flags".
bool is_utf8_string_loclen_flags(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)is_utf8_valid_partial_charReturns 0 if the sequence of bytes starting ats and looking no further thane - 1 is the UTF-8 encoding, as extended by Perl, for one or more code points. Otherwise, it returns 1 if there exists at least one non-empty sequence of bytes that when appended to sequences, starting at positione causes the entire sequence to be the well-formed UTF-8 of some code point; otherwise returns 0.
In other words this returns TRUE ifs points to a partial UTF-8-encoded code point.
This is useful when a fixed-length buffer is being tested for being well-formed UTF-8, but the final few bytes in it don't comprise a full character; that is, it is split somewhere in the middle of the final code point's UTF-8 representation. (Presumably when the buffer is refreshed with the next chunk of data, the new first bytes will complete the partial code point.) This function is used to verify that the final bytes in the current buffer are in fact the legal beginning of some code point, so that if they aren't, the failure can be signalled without having to wait for the next read.
bool is_utf8_valid_partial_char(const U8 * const s0, const U8 * const e)is_utf8_valid_partial_char_flagsLike"is_utf8_valid_partial_char", it returns a boolean giving whether or not the input is a valid UTF-8 encoded partial character, but it takes an extra parameter,flags, which can further restrict which code points are considered valid.
Ifflags is 0, this behaves identically to"is_utf8_valid_partial_char". Otherwiseflags can be any combination of theUTF8_DISALLOW_foo flags accepted by"utf8n_to_uvchr". If there is any sequence of bytes that can complete the input partial character in such a way that a non-prohibited character is formed, the function returns TRUE; otherwise FALSE. Non character code points cannot be determined based on partial character input. But many of the other possible excluded types can be determined from just the first one or two bytes.
bool is_utf8_valid_partial_char_flags(const U8 * const s0, const U8 * const e, const U32 flags)LATIN1_TO_NATIVEReturns the native equivalent of the input Latin-1 code point (including ASCII and control characters) given bych. Thus,LATIN1_TO_NATIVE(66) on EBCDIC platforms returns 194. These each represent the character"B" on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
For conversion of code points potentially larger than will fit in a character, use"UNI_TO_NATIVE".
U8 LATIN1_TO_NATIVE(U8 ch)NATIVE_TO_LATIN1Returns the Latin-1 (including ASCII and control characters) equivalent of the input native code point given bych. Thus,NATIVE_TO_LATIN1(193) on EBCDIC platforms returns 65. These each represent the character"A" on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
For conversion of code points potentially larger than will fit in a character, use"NATIVE_TO_UNI".
U8 NATIVE_TO_LATIN1(U8 ch)NATIVE_TO_UNIReturns the Unicode equivalent of the input native code point given bych. Thus,NATIVE_TO_UNI(195) on EBCDIC platforms returns 67. These each represent the character"C" on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
UV NATIVE_TO_UNI(UV ch)pv_uni_displayBuild to the scalardsv a displayable version of the UTF-8 encoded stringspv, lengthlen, the displayable version being at mostpvlim bytes long (if longer, the rest is truncated and"..." will be appended).
Theflags argument can haveUNI_DISPLAY_ISPRINT set to displayisPRINT()able characters as themselves,UNI_DISPLAY_BACKSLASH to display the\\[nrfta\\] as the backslashed versions (like"\n") (UNI_DISPLAY_BACKSLASH is preferred overUNI_DISPLAY_ISPRINT for"\\").UNI_DISPLAY_QQ (and its aliasUNI_DISPLAY_REGEX) have bothUNI_DISPLAY_BACKSLASH andUNI_DISPLAY_ISPRINT turned on.
Additionally, there is nowUNI_DISPLAY_BACKSPACE which allows\b for a backspace, but only whenUNI_DISPLAY_BACKSLASH also is set.
The pointer to the PV of thedsv is returned.
See also"sv_uni_display".
char * pv_uni_display(SV *dsv, const U8 *spv, STRLEN len, STRLEN pvlim, UV flags)REPLACEMENT_CHARACTER_UTF8This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode REPLACEMENT CHARACTER (U+FFFD) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms.sizeof(REPLACEMENT_CHARACTER_UTF8) - 1 can be used to get its length in bytes.
sv_cat_decodeencoding is assumed to be anEncode object, the PV ofssv is assumed to be octets in that encoding and decoding the input starts from the position which(PV + *offset) pointed to.dsv will be concatenated with the decoded UTF-8 string fromssv. Decoding will terminate when the stringtstr appears in decoding output or the input ends on the PV ofssv. The value whichoffset points will be modified to the last input position onssv.
Returns TRUE if the terminator was found, else returns FALSE.
bool sv_cat_decode(SV *dsv, SV *encoding, SV *ssv, int *offset, char *tstr, int tlen)sv_recode_to_utf8encoding is assumed to be anEncode object, on entry the PV ofsv is assumed to be octets in that encoding, andsv will be converted into Unicode (and UTF-8).
Ifsv already is UTF-8 (or if it is notPOK), or ifencoding is not a reference, nothing is done tosv. Ifencoding is not anEncode::XS Encoding object, bad things will happen. (Seeencoding andEncode.)
The PV ofsv is returned.
char * sv_recode_to_utf8(SV *sv, SV *encoding)sv_uni_displayBuild to the scalardsv a displayable version of the scalarsv, the displayable version being at mostpvlim bytes long (if longer, the rest is truncated and "..." will be appended).
Theflags argument is as in"pv_uni_display"().
The pointer to the PV of thedsv is returned.
char * sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim, UV flags)UNICODE_IS_NONCHARReturns a boolean as to whether or notuv is one of the Unicode non-character code points
bool UNICODE_IS_NONCHAR(const UV uv)UNICODE_IS_REPLACEMENTReturns a boolean as to whether or notuv is the Unicode REPLACEMENT CHARACTER
bool UNICODE_IS_REPLACEMENT(const UV uv)UNICODE_IS_SUPERReturns a boolean as to whether or notuv is above the maximum legal Unicode code point of U+10FFFF.
bool UNICODE_IS_SUPER(const UV uv)UNICODE_IS_SURROGATEReturns a boolean as to whether or notuv is one of the Unicode surrogate code points
bool UNICODE_IS_SURROGATE(const UV uv)UNICODE_REPLACEMENTEvaluates to 0xFFFD, the code point of the Unicode REPLACEMENT CHARACTER
UNI_TO_NATIVEReturns the native equivalent of the input Unicode code point given bych. Thus,UNI_TO_NATIVE(68) on EBCDIC platforms returns 196. These each represent the character"D" on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
UV UNI_TO_NATIVE(UV ch)UTF8_CHK_SKIPThis is a safer version of"UTF8SKIP", but still not as safe as"UTF8_SAFE_SKIP". This version doesn't blindly assume that the input string pointed to bys is well-formed, but verifies that there isn't a NUL terminating character before the expected end of the next character ins. The lengthUTF8_CHK_SKIP returns stops just before any such NUL.
Perl tends to add NULs, as an insurance policy, after the end of strings in SV's, so it is likely that using this macro will prevent inadvertent reading beyond the end of the input buffer, even if it is malformed UTF-8.
This macro is intended to be used by XS modules where the inputs could be malformed, and it isn't feasible to restructure to use the safer"UTF8_SAFE_SKIP", for example when interfacing with a C library.
STRLEN UTF8_CHK_SKIP(char* s)utf8_distanceReturns the number of UTF-8 characters between the UTF-8 pointersa andb.
WARNING: use only if you *know* that the pointers point inside the same UTF-8 buffer.
IV utf8_distance(const U8 *a, const U8 *b)utf8_hopReturn the UTF-8 pointers displaced byoff characters, either forward (ifoff is positive) or backward (if negative).s does not need to be pointing to the starting byte of a character. If it isn't, one count ofoff will be used up to get to the start of the next character for forward hops, and to the start of the current character for negative ones.
WARNING: Prefer"utf8_hop_safe" to this one.
Do NOT use this function unless youknowoff is within the UTF-8 data pointed to bysand that on entrys is aligned on the first byte of a character or just after the last byte of a character.
U8 * utf8_hop(const U8 *s, SSize_t off)utf8_hop_backReturn the UTF-8 pointers displaced by up tooff characters, backward.s does not need to be pointing to the starting byte of a character. If it isn't, one count ofoff will be used up to get to that start.
off must be non-positive.
s must be after or equal tostart.
When moving backward it will not move beforestart.
Will not exceed this limit even if the string is not valid "UTF-8".
U8 * utf8_hop_back(const U8 *s, SSize_t off, const U8 *start)utf8_hop_forwardReturn the UTF-8 pointers displaced by up tooff characters, forward.s does not need to be pointing to the starting byte of a character. If it isn't, one count ofoff will be used up to get to the start of the next character.
off must be non-negative.
s must be before or equal toend.
When moving forward it will not move beyondend.
Will not exceed this limit even if the string is not valid "UTF-8".
U8 * utf8_hop_forward(const U8 *s, SSize_t off, const U8 *end)utf8_hop_safeReturn the UTF-8 pointers displaced by up tooff characters, either forward or backward.s does not need to be pointing to the starting byte of a character. If it isn't, one count ofoff will be used up to get to the start of the next character for forward hops, and to the start of the current character for negative ones.
When moving backward it will not move beforestart.
When moving forward it will not move beyondend.
Will not exceed those limits even if the string is not valid "UTF-8".
U8 * utf8_hop_safe(const U8 *s, SSize_t off, const U8 *start, const U8 *end)UTF8_IS_INVARIANTEvaluates to 1 if the bytec represents the same character when encoded in UTF-8 as when not; otherwise evaluates to 0. UTF-8 invariant characters can be copied as-is when converting to/from UTF-8, saving time.
In spite of the name, this macro gives the correct result if the input string from whichc comes is not encoded in UTF-8.
See"UVCHR_IS_INVARIANT" for checking if a UV is invariant.
bool UTF8_IS_INVARIANT(char c)UTF8_IS_NONCHAREvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents one of the Unicode non-character code points; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation.
bool UTF8_IS_NONCHAR(const U8 *s, const U8 *e)UTF8_IS_REPLACEMENTEvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents the Unicode REPLACEMENT CHARACTER; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation.
bool UTF8_IS_REPLACEMENT(const U8 *s, const U8 *e)UTF8_IS_SUPERRecall that Perl recognizes an extension to UTF-8 that can encode code points larger than the ones defined by Unicode, which are 0..0x10FFFF.
This macro evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are from this UTF-8 extension; otherwise it evaluates to 0. If non-zero, the return is how many bytes starting ats comprise the code point's representation.
0 is returned if the bytes are not well-formed extended UTF-8, or if they represent a code point that cannot fit in a UV on the current platform. Hence this macro can give different results when run on a 64-bit word machine than on one with a 32-bit word size.
Note that it is illegal in Perl to have code points that are larger than what can fit in an IV on the current machine; and illegal in Unicode to have any that this macro matches
bool UTF8_IS_SUPER(const U8 *s, const U8 *e)UTF8_IS_SURROGATEEvaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents one of the Unicode surrogate code points; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation.
bool UTF8_IS_SURROGATE(const U8 *s, const U8 *e)utf8_lengthReturns the number of characters in the sequence of UTF-8-encoded bytes starting ats and ending at the byte just beforee. If <s> and <e> point to the same place, it returns 0 with no warning raised.
Ife < s or if the scan would end up paste, it raises a UTF8 warning and returns the number of valid characters.
STRLEN utf8_length(const U8 *s0, const U8 *e)UTF8_MAXBYTESThe maximum width of a single UTF-8 encoded character, in bytes.
NOTE: Strictly speaking Perl's UTF-8 should not be called UTF-8 since UTF-8 is an encoding of Unicode, and Unicode's upper limit, 0x10FFFF, can be expressed with 4 bytes. However, Perl thinks of UTF-8 as a way to encode non-negative integers in a binary format, even those above Unicode.
UTF8_MAXBYTES_CASEThe maximum number of UTF-8 bytes a single Unicode character can uppercase/lowercase/titlecase/fold into.
utf8ness_tThis typedef is used by several core functions that return PV strings, to indicate the UTF-8ness of those strings.
(If you write a new function, you probably should instead return the PV in an SV with the UTF-8 flag of the SV properly set, rather than use this mechanism.)
The possible values this can be are:
UTF8NESS_YESThis means the string definitely should be treated as a sequence of UTF-8-encoded characters.
Most code that needs to handle this typedef should be of the form:
if (utf8ness_flag == UTF8NESS_YES) { treat as utf8; // like turning on an SV UTF-8 flag}UTF8NESS_NOThis means the string definitely should be treated as a sequence of bytes, not encoded as UTF-8.
UTF8NESS_IMMATERIALThis means it is equally valid to treat the string as bytes, or as UTF-8 characters; use whichever way you want. This happens when the string consists entirely of characters which have the same representation whether encoded in UTF-8 or not.
UTF8NESS_UNKNOWNThis means it is unknown how the string should be treated. No core function will ever return this value to a non-core caller. Instead, it is used by the caller to initialize a variable to a non-legal value. A typical call will look like:
utf8ness_t string_is_utf8 = UTF8NESS_UNKNOWNconst char * string = foo(arg1, arg2, ..., &string_is_utf8);if (string_is_utf8 == UTF8NESS_YES) { do something for UTF-8;}The following relationships hold between the enum values:
utf8n_to_uvchrTHIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use"utf8_to_uvchr_buf"() rather than call this directly.
Bottom level UTF-8 decode routine. Returns the native code point value of the first character in the strings, which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer thancurlen bytes;*retlen (ifretlen isn't NULL) will be set to the length, in bytes, of that character.
The value offlags determines the behavior whens does not point to a well-formed UTF-8 character. Ifflags is 0, encountering a malformation causes zero to be returned and*retlen is set so that (s +*retlen) is the next possible position ins that could begin a non-malformed character. Also, if UTF-8 warnings haven't been lexically disabled, a warning is raised. Some UTF-8 input sequences may contain multiple malformations. This function tries to find every possible one in each call, so multiple warnings can be raised for the same sequence.
Various ALLOW flags can be set inflags to allow (and not warn on) individual types of malformations, such as the sequence being overlong (that is, when there is a shorter sequence that can express the same code point; overlong sequences are expressly forbidden in the UTF-8 standard due to potential security issues). Another malformation example is the first byte of a character not being a legal first byte. Seeutf8.h for the list of such flags. Even if allowed, this function generally returns the Unicode REPLACEMENT CHARACTER when it encounters a malformation. There are flags inutf8.h to override this behavior for the overlong malformations, but don't do that except for very specialized purposes.
TheUTF8_CHECK_ONLY flag overrides the behavior when a non-allowed (by other flags) malformation is found. If this flag is set, the routine assumes that the caller will raise a warning, and this function will silently just setretlen to-1 (cast toSTRLEN) and return zero.
Note that this API requires disambiguation between successful decoding aNUL character, and an error return (unless theUTF8_CHECK_ONLY flag is set), as in both cases, 0 is returned, and, depending on the malformation,retlen may be set to 1. To disambiguate, upon a zero return, see if the first byte ofs is 0 as well. If so, the input was aNUL; if not, the input had an error. Or you can use"utf8n_to_uvchr_error".
Certain code points are considered problematic. These are Unicode surrogates, Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF. By default these are considered regular code points, but certain situations warrant special handling for them, which can be specified using theflags parameter. Ifflags containsUTF8_DISALLOW_ILLEGAL_INTERCHANGE, all three classes are treated as malformations and handled as such. The flagsUTF8_DISALLOW_SURROGATE,UTF8_DISALLOW_NONCHAR, andUTF8_DISALLOW_SUPER (meaning above the legal Unicode maximum) can be set to disallow these categories individually.UTF8_DISALLOW_ILLEGAL_INTERCHANGE restricts the allowed inputs to the strict UTF-8 traditionally defined by Unicode. UseUTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE to use the strictness definition given byUnicode Corrigendum #9. The difference between traditional strictness and C9 strictness is that the latter does not forbid non-character code points. (They are still discouraged, however.) For more discussion see"Noncharacter code points" in perlunicode.
The flagsUTF8_WARN_ILLEGAL_INTERCHANGE,UTF8_WARN_ILLEGAL_C9_INTERCHANGE,UTF8_WARN_SURROGATE,UTF8_WARN_NONCHAR, andUTF8_WARN_SUPER will cause warning messages to be raised for their respective categories, but otherwise the code points are considered valid (not malformations). To get a category to both be treated as a malformation and raise a warning, specify both the WARN and DISALLOW flags. (But note that warnings are not raised if lexically disabled nor ifUTF8_CHECK_ONLY is also specified.)
Extremely high code points were never specified in any standard, and require an extension to UTF-8 to express, which Perl does. It is likely that programs written in something other than Perl would not be able to read files that contain these; nor would Perl understand files written by something that uses a different extension. For these reasons, there is a separate set of flags that can warn and/or disallow these extremely high code points, even if other above-Unicode ones are accepted. They are theUTF8_WARN_PERL_EXTENDED andUTF8_DISALLOW_PERL_EXTENDED flags. For more information see"UTF8_GOT_PERL_EXTENDED". Of courseUTF8_DISALLOW_SUPER will treat all above-Unicode code points, including these, as malformations. (Note that the Unicode standard considers anything above 0x10FFFF to be illegal, but there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym forUTF8_WARN_PERL_EXTENDED is retained for backward compatibility:UTF8_WARN_ABOVE_31_BIT. Similarly,UTF8_DISALLOW_ABOVE_31_BIT is usable instead of the more accurately namedUTF8_DISALLOW_PERL_EXTENDED. The names are misleading because these flags can apply to code points that actually do fit in 31 bits. This happens on EBCDIC platforms, and sometimes when theoverlong malformation is also present. The new names accurately describe the situation in all cases.
All other code points corresponding to Unicode characters, including private use and those yet to be assigned, are never considered malformed and never warn.
UV utf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags)utf8n_to_uvchr_errorTHIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use"utf8_to_uvchr_buf"() rather than call this directly.
This function is for code that needs to know what the precise malformation(s) are when an error is found. If you also need to know the generated warning messages, use"utf8n_to_uvchr_msgs"() instead.
It is like"utf8n_to_uvchr" but it takes an extra parameter placed after all the others,errors. If this parameter is 0, this function behaves identically to"utf8n_to_uvchr". Otherwise,errors should be a pointer to aU32 variable, which this function sets to indicate any errors found. Upon return, if*errors is 0, there were no errors found. Otherwise,*errors is the bit-wiseOR of the bits described in the list below. Some of these bits will be set if a malformation is found, even if the inputflags parameter indicates that the given malformation is allowed; those exceptions are noted:
UTF8_GOT_PERL_EXTENDEDThe input sequence is not standard UTF-8, but a Perl extension. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_PERL_EXTENDED or theUTF8_WARN_PERL_EXTENDED flags.
Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard, and so some extension must be used to express them. Perl uses a natural extension to UTF-8 to represent the ones up to 2**36-1, and invented a further extension to represent even higher ones, so that any code point that fits in a 64-bit word can be represented. Text using these extensions is not likely to be portable to non-Perl code. We lump both of these extensions together and refer to them as Perl extended UTF-8. There exist other extensions that people have invented, incompatible with Perl's.
On EBCDIC platforms starting in Perl v5.24, the Perl extension for representing extremely high code points kicks in at 0x3FFF_FFFF (2**30 -1), which is lower than on ASCII. Prior to that, code points 2**31 and higher were simply unrepresentable, and a different, incompatible method was used to represent code points between 2**30 and 2**31 - 1.
On both platforms, ASCII and EBCDIC,UTF8_GOT_PERL_EXTENDED is set if Perl extended UTF-8 is used.
In earlier Perls, this bit was namedUTF8_GOT_ABOVE_31_BIT, which you still may use for backward compatibility. That name is misleading, as this flag may be set when the code point actually does fit in 31 bits. This happens on EBCDIC platforms, and sometimes when theoverlong malformation is also present. The new name accurately describes the situation in all cases.
UTF8_GOT_CONTINUATIONThe input sequence was malformed in that the first byte was a UTF-8 continuation byte.
UTF8_GOT_EMPTYThe inputcurlen parameter was 0.
UTF8_GOT_LONGThe input sequence was malformed in that there is some other sequence that evaluates to the same code point, but that sequence is shorter than this one.
Until Unicode 3.1, it was legal for programs to accept this malformation, but it was discovered that this created security issues.
UTF8_GOT_NONCHARThe code point represented by the input UTF-8 sequence is for a Unicode non-character code point. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_NONCHAR or theUTF8_WARN_NONCHAR flags.
UTF8_GOT_NON_CONTINUATIONThe input sequence was malformed in that a non-continuation type byte was found in a position where only a continuation type one should be. See also"UTF8_GOT_SHORT".
UTF8_GOT_OVERFLOWThe input sequence was malformed in that it is for a code point that is not representable in the number of bits available in an IV on the current platform.
UTF8_GOT_SHORTThe input sequence was malformed in thatcurlen is smaller than required for a complete sequence. In other words, the input is for a partial character sequence.
UTF8_GOT_SHORT andUTF8_GOT_NON_CONTINUATION both indicate a too short sequence. The difference is thatUTF8_GOT_NON_CONTINUATION indicates always that there is an error, whileUTF8_GOT_SHORT means that an incomplete sequence was looked at. If no other flags are present, it means that the sequence was valid as far as it went. Depending on the application, this could mean one of three things:
Thecurlen length parameter passed in was too small, and the function was prevented from examining all the necessary bytes.
The buffer being looked at is based on reading data, and the data received so far stopped in the middle of a character, so that the next read will read the remainder of this character. (It is up to the caller to deal with the split bytes somehow.)
This is a real error, and the partial sequence is all we're going to get.
UTF8_GOT_SUPERThe input sequence was malformed in that it is for a non-Unicode code point; that is, one above the legal Unicode maximum. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_SUPER or theUTF8_WARN_SUPER flags.
UTF8_GOT_SURROGATEThe input sequence was malformed in that it is for a -Unicode UTF-16 surrogate code point. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_SURROGATE or theUTF8_WARN_SURROGATE flags.
To do your own error handling, call this function with theUTF8_CHECK_ONLY flag to suppress any warnings, and then examine the*errors return.
UV utf8n_to_uvchr_error(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags, U32 *errors)utf8n_to_uvchr_msgsTHIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use"utf8_to_uvchr_buf"() rather than call this directly.
This function is for code that needs to know what the precise malformation(s) are when an error is found, and wants the corresponding warning and/or error messages to be returned to the caller rather than be displayed. All messages that would have been displayed if all lexical warnings are enabled will be returned.
It is just like"utf8n_to_uvchr_error" but it takes an extra parameter placed after all the others,msgs. If this parameter is 0, this function behaves identically to"utf8n_to_uvchr_error". Otherwise,msgs should be a pointer to anAV * variable, in which this function creates a new AV to contain any appropriate messages. The elements of the array are ordered so that the first message that would have been displayed is in the 0th element, and so on. Each element is a hash with three key-value pairs, as follows:
textThe text of the message as aSVpv.
warn_categoriesThe warning category (or categories) packed into aSVuv.
flagA single flag bit associated with this message, in aSVuv. The bit corresponds to some bit in the*errors return value, such asUTF8_GOT_LONG.
It's important to note that specifying this parameter as non-null will cause any warnings this function would otherwise generate to be suppressed, and instead be placed in*msgs. The caller can check the lexical warnings state (or not) when choosing what to do with the returned messages.
If the flagUTF8_CHECK_ONLY is passed, no warnings are generated, and hence no AV is created.
The caller, of course, is responsible for freeing any returned AV.
UV utf8n_to_uvchr_msgs(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags, U32 *errors, AV **msgs)UTF8_SAFE_SKIPreturns 0 ifs >= e; otherwise returns the number of bytes in the UTF-8 encoded character whose first byte is pointed to bys. But it never returns beyonde. On DEBUGGING builds, it asserts thats <= e.
STRLEN UTF8_SAFE_SKIP(char* s, char* e)UTF8SKIPreturns the number of bytes a non-malformed UTF-8 encoded character whose first (perhaps only) byte is pointed to bys.
If there is a possibility of malformed input, use instead:
"UTF8_SAFE_SKIP" if you know the maximum ending pointer in the buffer pointed to bys; or"UTF8_CHK_SKIP" if you don't know it.It is better to restructure your code so the end pointer is passed down so that you know what it actually is at the point of this call, but if that isn't possible,"UTF8_CHK_SKIP" can minimize the chance of accessing beyond the end of the input buffer.
STRLEN UTF8SKIP(char* s)UTF8_SKIPThis is a synonym for"UTF8SKIP"
STRLEN UTF8_SKIP(char* s)utf8_to_bytesNOTE:utf8_to_bytes isexperimental and may change or be removed without notice.
Converts a string"s" of length*lenp from UTF-8 into native byte encoding. Unlike"bytes_to_utf8", this over-writes the original string, and updates*lenp to contain the new length. Returns zero on failure (leaving"s" unchanged) setting*lenp to -1.
Upon successful return, the number of variants in the string can be computed by having saved the value of*lenp before the call, and subtracting the after-call value of*lenp from it.
If you need a copy of the string, see"bytes_from_utf8".
U8 * utf8_to_bytes(U8 *s, STRLEN *lenp)utf8_to_uvchrDEPRECATED! It is planned to removeutf8_to_uvchr from a future release of Perl. Do not use it for new code; remove it from existing code.
Returns the native code point of the first character in the strings which is assumed to be in UTF-8 encoding;retlen will be set to the length, in bytes, of that character.
Some, but not all, UTF-8 malformations are detected, and in fact, some malformed input could cause reading beyond the end of the input buffer, which is why this function is deprecated. Use"utf8_to_uvchr_buf" instead.
Ifs points to one of the detected malformations, and UTF8 warnings are enabled, zero is returned and*retlen is set (ifretlen isn'tNULL) to -1. If those warnings are off, the computed value if well-defined (or the Unicode REPLACEMENT CHARACTER, if not) is silently returned, and*retlen is set (ifretlen isn't NULL) so that (s +*retlen) is the next possible position ins that could begin a non-malformed character. See"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvchr(const U8 *s, STRLEN *retlen)utf8_to_uvchr_bufReturns the native code point of the first character in the strings which is assumed to be in UTF-8 encoding;send points to 1 beyond the end ofs.*retlen will be set to the length, in bytes, of that character.
Ifs does not point to a well-formed UTF-8 character and UTF8 warnings are enabled, zero is returned and*retlen is set (ifretlen isn'tNULL) to -1. If those warnings are off, the computed value, if well-defined (or the Unicode REPLACEMENT CHARACTER if not), is silently returned, and*retlen is set (ifretlen isn'tNULL) so that (s +*retlen) is the next possible position ins that could begin a non-malformed character. See"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvchr_buf(const U8 *s, const U8 *send, STRLEN *retlen)UVCHR_IS_INVARIANTEvaluates to 1 if the representation of code pointcp is the same whether or not it is encoded in UTF-8; otherwise evaluates to 0. UTF-8 invariant characters can be copied as-is when converting to/from UTF-8, saving time.cp is Unicode if above 255; otherwise is platform-native.
bool UVCHR_IS_INVARIANT(UV cp)UVCHR_SKIPreturns the number of bytes required to represent the code pointcp when encoded as UTF-8.cp is a native (ASCII or EBCDIC) code point if less than 255; a Unicode code point otherwise.
STRLEN UVCHR_SKIP(UV cp)uvchr_to_utf8_flagsAdds the UTF-8 representation of the native code pointuv to the end of the stringd;d should have at leastUVCHR_SKIP(uv)+1 (up toUTF8_MAXBYTES+1) free bytes available. The return value is the pointer to the byte after the end of the new character. In other words,
d = uvchr_to_utf8_flags(d, uv, flags);or, in most cases,
d = uvchr_to_utf8_flags(d, uv, 0);This is the Unicode-aware way of saying
*(d++) = uv;Ifflags is 0, this function accepts any code point from 0..IV_MAX as input.IV_MAX is typically 0x7FFF_FFFF in a 32-bit word.
Specifyingflags can further restrict what is allowed and not warned on, as follows:
Ifuv is a Unicode surrogate code point andUNICODE_WARN_SURROGATE is set, the function will raise a warning, provided UTF8 warnings are enabled. If insteadUNICODE_DISALLOW_SURROGATE is set, the function will fail and return NULL. If both flags are set, the function will both warn and return NULL.
Similarly, theUNICODE_WARN_NONCHAR andUNICODE_DISALLOW_NONCHAR flags affect how the function handles a Unicode non-character.
And likewise, theUNICODE_WARN_SUPER andUNICODE_DISALLOW_SUPER flags affect the handling of code points that are above the Unicode maximum of 0x10FFFF. Languages other than Perl may not be able to accept files that contain these.
The flagUNICODE_WARN_ILLEGAL_INTERCHANGE selects all three of the above WARN flags; andUNICODE_DISALLOW_ILLEGAL_INTERCHANGE selects all three DISALLOW flags.UNICODE_DISALLOW_ILLEGAL_INTERCHANGE restricts the allowed inputs to the strict UTF-8 traditionally defined by Unicode. Similarly,UNICODE_WARN_ILLEGAL_C9_INTERCHANGE andUNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE are shortcuts to select the above-Unicode and surrogate flags, but not the non-character ones, as defined inUnicode Corrigendum #9. See"Noncharacter code points" in perlunicode.
Extremely high code points were never specified in any standard, and require an extension to UTF-8 to express, which Perl does. It is likely that programs written in something other than Perl would not be able to read files that contain these; nor would Perl understand files written by something that uses a different extension. For these reasons, there is a separate set of flags that can warn and/or disallow these extremely high code points, even if other above-Unicode ones are accepted. They are theUNICODE_WARN_PERL_EXTENDED andUNICODE_DISALLOW_PERL_EXTENDED flags. For more information see"UTF8_GOT_PERL_EXTENDED". Of courseUNICODE_DISALLOW_SUPER will treat all above-Unicode code points, including these, as malformations. (Note that the Unicode standard considers anything above 0x10FFFF to be illegal, but there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym forUNICODE_WARN_PERL_EXTENDED is retained for backward compatibility:UNICODE_WARN_ABOVE_31_BIT. Similarly,UNICODE_DISALLOW_ABOVE_31_BIT is usable instead of the more accurately namedUNICODE_DISALLOW_PERL_EXTENDED. The names are misleading because on EBCDIC platforms,these flags can apply to code points that actually do fit in 31 bits. The new names accurately describe the situation in all cases.
U8 * uvchr_to_utf8_flags(U8 *d, UV uv, UV flags)uvchr_to_utf8_flags_msgsTHIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use"uvchr_to_utf8_flags"() rather than call this directly.
This function is for code that wants any warning and/or error messages to be returned to the caller rather than be displayed. All messages that would have been displayed if all lexical warnings are enabled will be returned.
It is just like"uvchr_to_utf8_flags" but it takes an extra parameter placed after all the others,msgs. If this parameter is 0, this function behaves identically to"uvchr_to_utf8_flags". Otherwise,msgs should be a pointer to anHV * variable, in which this function creates a new HV to contain any appropriate messages. The hash has three key-value pairs, as follows:
textThe text of the message as aSVpv.
warn_categoriesThe warning category (or categories) packed into aSVuv.
flagA single flag bit associated with this message, in aSVuv. The bit corresponds to some bit in the*errors return value, such asUNICODE_GOT_SURROGATE.
It's important to note that specifying this parameter as non-null will cause any warnings this function would otherwise generate to be suppressed, and instead be placed in*msgs. The caller can check the lexical warnings state (or not) when choosing what to do with the returned messages.
The caller, of course, is responsible for freeing any returned HV.
U8 * uvchr_to_utf8_flags_msgs(U8 *d, UV uv, UV flags, HV **msgs)uvchr_to_utf8Adds the UTF-8 representation of the native code pointuv to the end of the stringd;d should have at leastUVCHR_SKIP(uv)+1 (up toUTF8_MAXBYTES+1) free bytes available. The return value is the pointer to the byte after the end of the new character. In other words,
d = uvchr_to_utf8(d, uv);is the recommended wide native character-aware way of saying
*(d++) = uv;This function accepts any code point from 0..IV_MAX as input.IV_MAX is typically 0x7FFF_FFFF in a 32-bit word.
It is possible to forbid or warn on non-Unicode code points, or those that may be problematic by using"uvchr_to_utf8_flags".
U8 * uvchr_to_utf8(U8 *d, UV uv)C_ARRAY_ENDReturns a pointer to one element past the final element of the input C array.
void * C_ARRAY_END(void *a)C_ARRAY_LENGTHReturns the number of elements in the input C array (so you want your zero-based indices to be less than but not equal to).
STRLEN C_ARRAY_LENGTH(void *a)getcwd_svFillsv with current working directory
int getcwd_sv(SV *sv)IN_PERL_COMPILETIMEReturns 1 if this macro is being called during the compilation phase of the program; otherwise 0;
bool IN_PERL_COMPILETIMEIN_PERL_RUNTIMEReturns 1 if this macro is being called during the execution phase of the program; otherwise 0;
bool IN_PERL_RUNTIMEIS_SAFE_SYSCALLSame as"is_safe_syscall".
bool IS_SAFE_SYSCALL(NN const char *pv, STRLEN len, NN const char *what, NN const char *op_name)is_safe_syscallTest that the givenpv (with lengthlen) doesn't contain any internalNUL characters. If it does, seterrno toENOENT, optionally warn using thesyscalls category, and return FALSE.
Return TRUE if the name is safe.
what andop_name are used in any warning.
Used by theIS_SAFE_SYSCALL() macro.
bool is_safe_syscall(const char *pv, STRLEN len, const char *what, const char *op_name)my_setenvA wrapper for the C librarysetenv(3). Don't use the latter, as the perl version has desirable safeguards
void my_setenv(const char *nam, const char *val)newPADxVOPConstructs, checks and returns an op containing a pad offset.type is the opcode, which should be one ofOP_PADSV,OP_PADAV,OP_PADHV orOP_PADCV. The returned op will have theop_targ field set by thepadix argument.
This is convenient when constructing a large optree in nested function calls, as it avoids needing to store the pad op directly to set theop_targ field as a side-effect. For example
o = op_append_elem(OP_LINESEQ, o, newPADxVOP(OP_PADSV, 0, padix));OP * newPADxVOP(I32 type, I32 flags, PADOFFSET padix)phase_nameReturns the given phase's name as a NUL-terminated string.
For example, to print a stack trace that includes the current interpreter phase you might do:
const char* phase_name = phase_name(PL_phase);mess("This is weird. (Perl phase: %s)", phase_name);const char * const phase_name(enum perl_phase)PoisonPoisonWith(0xEF) for catching access to freed memory.
void Poison(void* dest, int nitems, type)PoisonFreePoisonWith(0xEF) for catching access to freed memory.
void PoisonFree(void* dest, int nitems, type)PoisonNewPoisonWith(0xAB) for catching access to allocated but uninitialized memory.
void PoisonNew(void* dest, int nitems, type)PoisonWithFill up memory with a byte pattern (a byte repeated over and over again) that hopefully catches attempts to access uninitialized memory.
void PoisonWith(void* dest, int nitems, type, U8 byte)StructCopyThis is an architecture-independent macro that does a shallow copy of one structure to another.
void StructCopy(type *src, type *dest, type)sv_destroyableDummy routine which reports that object can be destroyed when there is no sharing module present. It ignores its single SV argument, and returns 'true'. Exists to avoid test for aNULL function pointer and because it could potentially warn under some level of strict-ness.
bool sv_destroyable(SV *sv)sv_nosharingDummy routine which "shares" an SV when there is no sharing module present. Or "locks" it. Or "unlocks" it. In other words, ignores its single SV argument. Exists to avoid test for aNULL function pointer and because it could potentially warn under some level of strict-ness.
void sv_nosharing(SV *sv)new_versionReturns a new version object based on the passed in SV:
SV *sv = new_version(SV *ver);Does not alter the passed in ver SV. See "upg_version" if you want to upgrade the SV.
SV * new_version(SV *ver)PERL_REVISIONDEPRECATED! It is planned to removePERL_REVISION from a future release of Perl. Do not use it for new code; remove it from existing code.
The major number component of the perl interpreter currently being compiled or executing. This has been5 from 1993 into 2020.
Instead use one of the version comparison macros. See"PERL_VERSION_EQ".
PERL_SUBVERSIONDEPRECATED! It is planned to removePERL_SUBVERSION from a future release of Perl. Do not use it for new code; remove it from existing code.
The micro number component of the perl interpreter currently being compiled or executing. In stable releases this gives the dot release number for maintenance updates. In development releases this gives a tag for a snapshot of the status at various points in the development cycle.
Instead use one of the version comparison macros. See"PERL_VERSION_EQ".
PERL_VERSIONDEPRECATED! It is planned to removePERL_VERSION from a future release of Perl. Do not use it for new code; remove it from existing code.
The minor number component of the perl interpreter currently being compiled or executing. Between 1993 into 2020, this has ranged from 0 to 33.
Instead use one of the version comparison macros. See"PERL_VERSION_EQ".
PERL_VERSION_EQPERL_VERSION_GEPERL_VERSION_GTPERL_VERSION_LEPERL_VERSION_LTPERL_VERSION_NEReturns whether or not the perl currently being compiled has the specified relationship to the perl given by the parameters. For example,
#if PERL_VERSION_GT(5,24,2) code that will only be compiled on perls after v5.24.2#else fallback code#endifNote that this is usable in making compile-time decisions
You may use the special value '*' for the final number to mean ALL possible values for it. Thus,
#if PERL_VERSION_EQ(5,31,'*')means all perls in the 5.31 series. And
#if PERL_VERSION_NE(5,24,'*')means all perls EXCEPT 5.24 ones. And
#if PERL_VERSION_LE(5,9,'*')is effectively
#if PERL_VERSION_LT(5,10,0)This means you don't have to think so much when converting from the existing deprecatedPERL_VERSION to using this macro:
#if PERL_VERSION <= 9becomes
#if PERL_VERSION_LE(5,9,'*')bool PERL_VERSION_EQ(const U8 major, const U8 minor, const U8 patch)prescan_versionValidate that a given string can be parsed as a version object, but doesn't actually perform the parsing. Can use either strict or lax validation rules. Can optionally set a number of hint variables to save the parsing code some time when tokenizing.
const char * prescan_version(const char *s, bool strict, const char **errstr, bool *sqv, int *ssaw_decimal, int *swidth, bool *salpha)scan_versionReturns a pointer to the next character after the parsed version string, as well as upgrading the passed in SV to an RV.
Function must be called with an already existing SV like
sv = newSV(0);s = scan_version(s, SV *sv, bool qv);Performs some preprocessing to the string to ensure that it has the correct characteristics of a version. Flags the object if it contains an underscore (which denotes this is an alpha version). The boolean qv denotes that the version should be interpreted as if it had multiple decimals, even if it doesn't.
const char * scan_version(const char *s, SV *rv, bool qv)upg_versionIn-place upgrade of the supplied SV to a version object.
SV *sv = upg_version(SV *sv, bool qv);Returns a pointer to the upgraded SV. Set the boolean qv if you want to force this SV to be interpreted as an "extended" version.
SV * upg_version(SV *ver, bool qv)vcmpVersion object aware cmp. Both operands must already have been converted into version objects.
int vcmp(SV *lhv, SV *rhv)vnormalAccepts a version object and returns the normalized string representation. Call like:
sv = vnormal(rv);NOTE: you can pass either the object directly or the SV contained within the RV.
The SV returned has a refcount of 1.
SV * vnormal(SV *vs)vnumifyAccepts a version object and returns the normalized floating point representation. Call like:
sv = vnumify(rv);NOTE: you can pass either the object directly or the SV contained within the RV.
The SV returned has a refcount of 1.
SV * vnumify(SV *vs)vstringifyIn order to maintain maximum compatibility with earlier versions of Perl, this function will return either the floating point notation or the multiple dotted notation, depending on whether the original version contained 1 or more dots, respectively.
The SV returned has a refcount of 1.
SV * vstringify(SV *vs)vverifyValidates that the SV contains valid internal structure for a version object. It may be passed either the version object (RV) or the hash itself (HV). If the structure is valid, it returns the HV. If the structure is invalid, it returns NULL.
SV *hv = vverify(sv);Note that it only confirms the bare minimum structure (so as not to get confused by derived classes which may contain additional hash entries):
The SV is an HV or a reference to an HV
The hash contains a "version" key
The "version" key has a reference to an AV as its value
SV * vverify(SV *vs)In all these calls, theU32 wn parameters are warning category constants. You can see the ones currently available in"Category Hierarchy" in warnings, just capitalize all letters in the names and prefix them byWARN_. So, for example, the categoryvoid used in a perl program becomesWARN_VOID when used in XS code and passed to one of the calls below.
ckWARNckWARN2ckWARN3ckWARN4These return a boolean as to whether or not warnings are enabled for any of the warning category(ies) parameters:w,w1, ....
Should any of the categories by default be enabled even if not within the scope ofuse warnings, instead use the"ckWARN_d" macros.
The categories must be completely independent, one may not be subclassed from the other.
bool ckWARN (U32 w)bool ckWARN2(U32 w1, U32 w2)bool ckWARN3(U32 w1, U32 w2, U32 w3)bool ckWARN4(U32 w1, U32 w2, U32 w3, U32 w4)ckWARN_dckWARN2_dckWARN3_dckWARN4_dLike"ckWARN", but for use if and only if the warning category(ies) is by default enabled even if not within the scope ofuse warnings.
bool ckWARN_d (U32 w)bool ckWARN2_d(U32 w1, U32 w2)bool ckWARN3_d(U32 w1, U32 w2, U32 w3)bool ckWARN4_d(U32 w1, U32 w2, U32 w3, U32 w4)ck_warnerck_warner_dIf none of the warning categories given byerr are enabled, do nothing; otherwise call"warner" or"warner_nocontext" with the passed-in parameters;.
err must be one of the"packWARN",packWARN2,packWARN3,packWARN4 macros populated with the appropriate number of warning categories.
The two forms differ only in thatck_warner_d should be used if warnings for any of the categories are by default enabled.
NOTE:ck_warner must be explicitly called asPerl_ck_warner with anaTHX_ parameter.
NOTE:ck_warner_d must be explicitly called asPerl_ck_warner_d with anaTHX_ parameter.
void Perl_ck_warner(pTHX_ U32 err, const char *pat, ...)CLEAR_ERRSVClear the contents of$@, setting it to the empty string.
This replaces any read-only SV with a fresh SV and removes any magic.
void CLEAR_ERRSV()croakcroak_nocontextThese are XS interfaces to Perl'sdie function.
They take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message will be used as an exception, by default returning control to the nearest enclosingeval, but subject to modification by a$SIG{__DIE__} handler. In any case, these croak functions never return normally.
For historical reasons, ifpat is null then the contents ofERRSV ($@) will be used as an error message or object instead of building an error message from arguments. If you want to throw a non-string object, or build an error message in an SV yourself, it is preferable to use the"croak_sv" function, which does not involve clobberingERRSV.
The two forms differ only in thatcroak_nocontext does not take a thread context (aTHX) parameter. It is usually preferred as it takes up fewer bytes of code than plainPerl_croak, and time is rarely a critical resource when you are about to throw an exception.
NOTE:croak must be explicitly called asPerl_croak with anaTHX_ parameter.
void Perl_croak (pTHX_ const char *pat, ...)void croak_nocontext(const char *pat, ...)croak_no_modifyThis encapsulates a common reason for dying, generating terser object code than using the genericPerl_croak. It is exactly equivalent toPerl_croak(aTHX_ "%s", PL_no_modify) (which expands to something like "Modification of a read-only value attempted").
Less code used on exception code paths reduces CPU cache pressure.
void croak_no_modify()croak_svThis is an XS interface to Perl'sdie function.
baseex is the error message or object. If it is a reference, it will be used as-is. Otherwise it is used as a string, and if it does not end with a newline then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message or object will be used as an exception, by default returning control to the nearest enclosingeval, but subject to modification by a$SIG{__DIE__} handler. In any case, thecroak_sv function never returns normally.
To die with a simple string message, the"croak" function may be more convenient.
void croak_sv(SV *baseex)diedie_nocontextThese behave the same as"croak", except for the return type. They should be used only where theOP * return type is required. They never actually return.
The two forms differ only in thatdie_nocontext does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE:die must be explicitly called asPerl_die with anaTHX_ parameter.
OP * Perl_die (pTHX_ const char *pat, ...)OP * die_nocontext(const char *pat, ...)die_svThis behaves the same as"croak_sv", except for the return type. It should be used only where theOP * return type is required. The function never actually returns.
OP * die_sv(SV *baseex)ERRSVReturns the SV for$@, creating it if needed.
SV * ERRSVfatal_warnerLike"warner" except that it acts as if fatal warnings are enabled for the warning.
If called when there are pending compilation errors this function may return.
This is currently used to generate "used only once" fatal warnings since the COP where the name being reported is no longer the current COP when the warning is generated and may be useful for similar cases.
err must be one of the"packWARN",packWARN2,packWARN3,packWARN4 macros populated with the appropriate number of warning categories.
NOTE:fatal_warner must be explicitly called asPerl_fatal_warner with anaTHX_ parameter.
void Perl_fatal_warner(pTHX_ U32 err, const char *pat, ...)packWARNpackWARN2packWARN3packWARN4These macros are used to pack warning categories into a single U32 to pass to macros and functions that take a warning category parameter. The number of categories to pack is given by the name, with a corresponding number of category parameters passed.
U32 packWARN (U32 w1)U32 packWARN2(U32 w1, U32 w2)U32 packWARN3(U32 w1, U32 w2, U32 w3)U32 packWARN4(U32 w1, U32 w2, U32 w3, U32 w4)SANE_ERRSVClean up ERRSV so we can safely set it.
This replaces any read-only SV with a fresh writable copy and removes any magic.
void SANE_ERRSV()vcroakThis is an XS interface to Perl'sdie function.
pat andargs are a sprintf-style format pattern and encapsulated argument list. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message will be used as an exception, by default returning control to the nearest enclosingeval, but subject to modification by a$SIG{__DIE__} handler. In any case, thecroak function never returns normally.
For historical reasons, ifpat is null then the contents ofERRSV ($@) will be used as an error message or object instead of building an error message from arguments. If you want to throw a non-string object, or build an error message in an SV yourself, it is preferable to use the"croak_sv" function, which does not involve clobberingERRSV.
void vcroak(const char *pat, va_list *args)vfatal_warnerThis is like"fatal_warner" butargs are an encapsulated argument list.
void vfatal_warner(U32 err, const char *pat, va_list *args)vwarnThis is an XS interface to Perl'swarn function.
This is like"warn", butargs are an encapsulated argument list.
Unlike with"vcroak",pat is not permitted to be null.
void vwarn(const char *pat, va_list *args)vwarnerThis is like"warner", butargs are an encapsulated argument list.
void vwarner(U32 err, const char *pat, va_list *args)warnwarn_nocontextThese are XS interfaces to Perl'swarn function.
They take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message or object will by default be written to standard error, but this is subject to modification by a$SIG{__WARN__} handler.
Unlike with"croak",pat is not permitted to be null.
The two forms differ only in thatwarn_nocontext does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE:warn must be explicitly called asPerl_warn with anaTHX_ parameter.
void Perl_warn (pTHX_ const char *pat, ...)void warn_nocontext(const char *pat, ...)warnerwarner_nocontextThese output a warning of the specified category (or categories) given byerr, using the sprintf-style format patternpat, and argument list.
err must be one of the"packWARN",packWARN2,packWARN3,packWARN4 macros populated with the appropriate number of warning categories. If any of the warning categories they specify is fatal, a fatal exception is thrown.
In any event a message is generated by the pattern and arguments. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message or object will by default be written to standard error, but this is subject to modification by a$SIG{__WARN__} handler.
pat is not permitted to be null.
The two forms differ only in thatwarner_nocontext does not take a thread context (aTHX) parameter, so is used in situations where the caller doesn't already have the thread context.
These functions differ from the similarly named"warn" functions, in that the latter are for XS code to unconditionally display a warning, whereas these are for code that may be compiling a perl program, and does extra checking to see if the warning should be fatal.
NOTE:warner must be explicitly called asPerl_warner with anaTHX_ parameter.
void Perl_warner (pTHX_ U32 err, const char *pat, ...)void warner_nocontext(U32 err, const char *pat, ...)warn_svThis is an XS interface to Perl'swarn function.
baseex is the error message or object. If it is a reference, it will be used as-is. Otherwise it is used as a string, and if it does not end with a newline then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message or object will by default be written to standard error, but this is subject to modification by a$SIG{__WARN__} handler.
To warn with a simple string message, the"warn" function may be more convenient.
void warn_sv(SV *baseex)xsubpp compiles XS code into C. See"xsubpp" in perlutil.
axVariable which is setup byxsubpp to indicate the stack base offset, used by theST,XSprePUSH andXSRETURN macros. ThedMARK macro must be called prior to setup theMARK variable.
Stack_off_t axCLASSVariable which is setup byxsubpp to indicate the class name for a C++ XS constructor. This is always achar*. See"THIS".
char* CLASSdAXSets up theax variable. This is usually handled automatically byxsubpp by callingdXSARGS.
dAX;dAXMARKSets up theax variable and stack marker variablemark. This is usually handled automatically byxsubpp by callingdXSARGS.
dAXMARK;dITEMSSets up theitems variable. This is usually handled automatically byxsubpp by callingdXSARGS.
dITEMS;dMY_CXT_SVNow a placeholder that declares nothing
dMY_CXT_SV;dUNDERBARSets up any variable needed by theUNDERBAR macro. It used to definepadoff_du, but it is currently a noop. However, it is strongly advised to still use it for ensuring past and future compatibility.
dUNDERBAR;dXSARGSSets up stack and mark pointers for an XSUB, callingdSP anddMARK. Sets up theax anditems variables by callingdAX anddITEMS. This is usually handled automatically byxsubpp.
dXSARGS;dXSI32Sets up theix variable for an XSUB which has aliases. This is usually handled automatically byxsubpp.
dXSI32;itemsVariable which is setup byxsubpp to indicate the number of items on the stack. See"Variable-length Parameter Lists" in perlxs.
Stack_off_t itemsixVariable which is setup byxsubpp to indicate which of an XSUB's aliases was used to invoke it. See"The ALIAS: Keyword" in perlxs.
I32 ixRETVALVariable which is setup byxsubpp to hold the return value for an XSUB. This is always the proper type for the XSUB. See"The RETVAL Variable" in perlxs.
type RETVALSTUsed to access elements on the XSUB's stack.
SV* ST(int ix)THISVariable which is setup byxsubpp to designate the object in a C++ XSUB. This is always the proper type for the C++ object. See"CLASS" and"Using XS With C++" in perlxs.
type THISUNDERBARThe SV* corresponding to the$_ variable. Works even if there is a lexical$_ in scope.
XSMacro to declare an XSUB and its C parameter list. This is handled byxsubpp. It is the same as using the more explicitXS_EXTERNAL macro; the latter is preferred.
XS_EXTERNALMacro to declare an XSUB and its C parameter list explicitly exporting the symbols.
XS_INTERNALMacro to declare an XSUB and its C parameter list without exporting the symbols. This is handled byxsubpp and generally preferable over exporting the XSUB symbols unnecessarily.
XSPROTOMacro used by"XS_INTERNAL" and"XS_EXTERNAL" to declare a function prototype. You probably shouldn't be using this directly yourself.
The following functions have been flagged as part of the public API, but are currently undocumented. Use them at your own risk, as the interfaces are subject to change. Functions that are not listed in this document are not intended for public use, and should NOT be used under any circumstances.
If you feel you need to use one of these functions, first send email toperl5-porters@perl.org. It may be that there is a good reason for the function not being documented, and it should be removed from this list; or it may just be that no one has gotten around to documenting it. In the latter case, you will be asked to submit a patch to document the function. Once your patch is accepted, it will indicate that the interface is stable (unless it is explicitly marked otherwise) and usable by you.
clone_params_del do_open resume_compcv sv_dup_inc clone_params_new do_openn sv_dupNext are the API-flagged elements that are considered experimental. Using one of these is even more risky than plain undocumented ones. They are listed here because they should be listed somewhere (so their existence doesn't get lost) and this is the best place for them.
apply_attrs_string hv_store_flags thread_locale_initgv_fetchmethod_pv_flags leave_adjust_stacks thread_locale_termgv_fetchmethod_pvn_flags newXS_flags gv_fetchmethod_sv_flags savetmpsFinally are deprecated undocumented API elements. Do not use any for new code; remove all occurrences of all of these from existing code.
There are currently no items of this type
Until May 1997, this document was maintained by Jeff Okamoto <okamoto@corp.hp.com>. It is now maintained as part of Perl itself.
With lots of help and suggestions from Dean Roehrich, Malcolm Beattie, Andreas Koenig, Paul Hudson, Ilya Zakharevich, Paul Marquess, Neil Bowers, Matthew Green, Tim Bunce, Spider Boardman, Ulrich Pfeifer, Stephen McCamant, and Gurusamy Sarathy.
API Listing originally by Dean Roehrich <roehrich@cray.com>.
Updated to be autogenerated from comments in the source by Benjamin Stuhl.
config.h,perlapio,perlcall,perlclib,perlembed,perlfilter,perlguts,perlhacktips,perlintern,perlinterp,perliol,perlmroapi,perlreapi,perlreguts,perlxs
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