perlapi - autogenerated documentation for the perl public API
This file contains the documentation of the perl public API generated by embed.pl, specifically a listing of functions, macros, flags, and variables that may be used by extension writers. The interfaces of any functions that are not listed here are subject to change without notice. For this reason, blindly using functions listed in proto.h is to be avoided when writing extensions.
Note that all Perl API global variables must be referenced with thePL_ prefix. 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.
Note that Perl can be compiled and run under EBCDIC (Seeperlebcdic) or ASCII. 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 more bytes than in UTF-8.
Also, on some EBCDIC machines, functions that are documented as operating on US-ASCII (or Basic Latin in Unicode terminology) may in fact operate on all 256 characters in the EBCDIC range, not just the subset corresponding to US-ASCII.
The listing below is alphabetical, case insensitive.
A backward-compatible version ofGIMME_V which can only returnG_SCALAR orG_ARRAY; in a void context, it returnsG_SCALAR. Deprecated. UseGIMME_V instead.
U32GIMMEThe XSUB-writer's equivalent to Perl'swantarray. ReturnsG_VOID,G_SCALAR orG_ARRAY for void, scalar or list context, respectively.
U32GIMME_VUsed to indicate list context. SeeGIMME_V,GIMME andperlcall.
Indicates that arguments returned from a callback should be discarded. Seeperlcall.
Used to force a Perleval wrapper around a callback. Seeperlcall.
Indicates that no arguments are being sent to a callback. Seeperlcall.
Used to indicate scalar context. SeeGIMME_V,GIMME, andperlcall.
Used to indicate void context. SeeGIMME_V andperlcall.
Same asav_len(). Deprecated, useav_len() instead.
intAvFILL(AV* av)Clears an array, making it empty. Does not free the memory used by the array itself.
voidav_clear(AV *av)Push 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: this function is experimental and may change or be removed without notice.
voidav_create_and_push(AV **const avp, SV *const val)Unshifts 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: this function is experimental and may change or be removed without notice.
SV**av_create_and_unshift_one(AV **const avp, SV *const val)Deletes the element indexed bykey from the array. Returns the deleted element. Ifflags equalsG_DISCARD, the element is freed and null is returned.
SV*av_delete(AV *av, I32 key, I32 flags)Returns true if the element indexed bykey has been initialized.
This relies on the fact that uninitialized array elements are set to&PL_sv_undef.
boolav_exists(AV *av, I32 key)Pre-extend an array. Thekey is the index to which the array should be extended.
voidav_extend(AV *av, I32 key)Returns the SV at the specified index in the array. Thekey is the index. Iflval is set then the fetch will be part of a store. 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.
SV**av_fetch(AV *av, I32 key, I32 lval)Set the highest index in the array to the given number, equivalent to Perl's$#array = $fill;.
The number of elements in the an array will befill + 1 after av_fill() returns. If the array was previously shorter then the additional elements appended are set toPL_sv_undef. If the array was longer, then the excess elements are freed.av_fill(av, -1) is the same asav_clear(av).
voidav_fill(AV *av, I32 fill)Returns the highest index in the array. The number of elements in the array isav_len(av) + 1. Returns -1 if the array is empty.
I32av_len(const AV *av)Creates a new AV and populates it with a list of SVs. The SVs are copied into the array, so they may be freed after the call to av_make. The new AV will have a reference count of 1.
AV*av_make(I32 size, SV **strp)Pops an SV off the end of the array. Returns&PL_sv_undef if the array is empty.
SV*av_pop(AV *av)Pushes an SV onto the end of the array. The array will grow automatically to accommodate the addition. Likeav_store, this takes ownership of one reference count.
voidav_push(AV *av, SV *val)Shifts an SV off the beginning of the array. Returns&PL_sv_undef if the array is empty.
SV*av_shift(AV *av)Stores an SV in an array. The array index is specified askey. The return value will be NULL 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 the originalSV*. Note that the caller is responsible for suitably incrementing the reference count ofval before the call, and decrementing it if the function returned NULL.
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, I32 key, SV *val)Undefines the array. Frees the memory used by the array itself.
voidav_undef(AV *av)Unshift the given number ofundef values onto the beginning of the array. The array will grow automatically to accommodate the addition. You must then useav_store to assign values to these new elements.
voidav_unshift(AV *av, I32 num)Returns the AV of the specified Perl array.flags are passed togv_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: the perl_ form of this function is deprecated.
AV*get_av(const char *name, I32 flags)Creates a new AV. The reference count is set to 1.
AV*newAV()Sort an array. Here is an example:
sortsv(AvARRAY(av), av_len(av)+1, Perl_sv_cmp_locale);Currently this always uses mergesort. See sortsv_flags for a more flexible routine.
voidsortsv(SV** array, size_t num_elts, SVCOMPARE_t cmp)Sort an array, with various options.
voidsortsv_flags(SV** array, size_t num_elts, SVCOMPARE_t cmp, U32 flags)Performs a callback to the specified Perl sub. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_argv(const char* sub_name, I32 flags, char** argv)Performs a callback to the specified Perl method. The blessed object must be on the stack. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_method(const char* methname, I32 flags)Performs a callback to the specified Perl sub. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_pv(const char* sub_name, I32 flags)Performs a callback to the Perl sub whose name is in the SV. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_sv(SV* sv, VOL I32 flags)Opening bracket on a callback. SeeLEAVE andperlcall.
ENTER;Tells Perl toeval the given string and return an SV* result.
NOTE: the perl_ form of this function is deprecated.
SV*eval_pv(const char* p, I32 croak_on_error)Tells Perl toeval the string in the SV.
NOTE: the perl_ form of this function is deprecated.
I32eval_sv(SV* sv, I32 flags)Closing bracket for temporaries on a callback. SeeSAVETMPS andperlcall.
FREETMPS;Closing bracket on a callback. SeeENTER andperlcall.
LEAVE;Opening bracket for temporaries on a callback. SeeFREETMPS andperlcall.
SAVETMPS;Returns a boolean indicating whether the Cchar is a US-ASCII (Basic Latin) alphanumeric character (including underscore) or digit.
boolisALNUM(char ch)Returns a boolean indicating whether the Cchar is a US-ASCII (Basic Latin) alphabetic character.
boolisALPHA(char ch)Returns a boolean indicating whether the Cchar is a US-ASCII (Basic Latin) digit.
boolisDIGIT(char ch)Returns a boolean indicating whether the Cchar is a US-ASCII (Basic Latin) lowercase character.
boolisLOWER(char ch)Returns a boolean indicating whether the Cchar is a US-ASCII (Basic Latin) whitespace.
boolisSPACE(char ch)Returns a boolean indicating whether the Cchar is a US-ASCII (Basic Latin) uppercase character.
boolisUPPER(char ch)Converts the specified character to lowercase. Characters outside the US-ASCII (Basic Latin) range are viewed as not having any case.
chartoLOWER(char ch)Converts the specified character to uppercase. Characters outside the US-ASCII (Basic Latin) range are viewed as not having any case.
chartoUPPER(char ch)Create 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 uses COPY_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. If KEEP_PTR_TABLE is not set then perl_clone will kill the ptr_table using the functionptr_table_free(PL_ptr_table); PL_ptr_table = NULL;, reason to keep it around is if you want to dup some of your own variable who are outside the graph perl scans, example of this code is in threads.xs create
CLONEf_CLONE_HOST This is a win32 thing, it is ignored on unix, it tells perls 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)Returns the stash of the CV.
HV*CvSTASH(CV* cv)Usesstrlen to get the length ofname, then callsget_cvn_flags.
NOTE: the perl_ form of this function is deprecated.
CV*get_cv(const char* name, I32 flags)Returns 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.
NOTE: the perl_ form of this function is deprecated.
CV*get_cvn_flags(const char* name, STRLEN len, I32 flags)Clear 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 the CvOUTSIDE pointer, so that any anonymous children can still follow the full lexical scope chain.
voidcv_undef(CV* cv)Loads the module whose name is pointed to by the string part of name. Note that the actual module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". flags can be any of PERL_LOADMOD_DENY, PERL_LOADMOD_NOIMPORT, or PERL_LOADMOD_IMPORT_OPS (or 0 for no flags). ver, if specified, provides version semantics similar touse Foo::Bar VERSION. The optional trailing SV* arguments can be used to specify arguments to the module's import() method, similar touse Foo::Bar VERSION LIST. They must be terminated with a final NULL pointer. Note that this list can only be omitted when the PERL_LOADMOD_NOIMPORT flag has been used. Otherwise at least a single NULL pointer to designate the default import list is required.
voidload_module(U32 flags, SV* name, SV* ver, ...)Stub that provides thread hook for perl_destruct when there are no threads.
intnothreadhook()Allocates a new Perl interpreter. Seeperlembed.
PerlInterpreter*perl_alloc()Initializes a new Perl interpreter. Seeperlembed.
voidperl_construct(PerlInterpreter *my_perl)Shuts down a Perl interpreter. Seeperlembed.
intperl_destruct(PerlInterpreter *my_perl)Releases a Perl interpreter. Seeperlembed.
voidperl_free(PerlInterpreter *my_perl)Tells a Perl interpreter to parse a Perl script. Seeperlembed.
intperl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit, int argc, char** argv, char** env)Tells a Perl interpreter to run. Seeperlembed.
intperl_run(PerlInterpreter *my_perl)Tells 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: the perl_ form of this function is deprecated.
voidrequire_pv(const char* pv)Similar 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)Escapes at most the first "count" chars of pv and puts the results into dsv such that the size of the escaped string will not exceed "max" chars and will not contain any incomplete escape sequences.
If flags contains PERL_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 when PERL_PV_ESCAPE_NOCLEAR is set this will not occur.
If PERL_PV_ESCAPE_UNI is set then the input string is treated as Unicode, if PERL_PV_ESCAPE_UNI_DETECT is set then the input string is scanned usingis_utf8_string() to determine if it is Unicode.
If PERL_PV_ESCAPE_ALL is set then all input chars will be output using\x01F1 style escapes, otherwise only chars above 255 will be escaped using this style, other non printable chars will use octal or common escaped patterns like\n. If PERL_PV_ESCAPE_NOBACKSLASH then all chars below 255 will be treated as printable and will be output as literals.
If PERL_PV_ESCAPE_FIRSTCHAR is set then only the first char of the string will be escaped, regardles of max. If the string is utf8 and the chars value is >255 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 3 or more digit hex value.
If PERL_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 by dsv.
char*pv_escape(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, STRLEN * const escaped, const U32 flags)Converts a string into something presentable, handling escaping via pv_escape() and supporting quoting and ellipses.
If the PERL_PV_PRETTY_QUOTE flag is set then the result will be double quoted with any double quotes in the string escaped. Otherwise if the PERL_PV_PRETTY_LTGT flag is set then the result be wrapped in angle brackets.
If the PERL_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.
If start_color is non-null then it will be inserted after the opening quote (if there is one) but before the escaped text. If end_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 by dsv.
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)GV*gv_fetchmethod(HV* stash, const char* name)The engine implementing pack() Perl function. Note: parameters next_in_list and flags are not used. This call should not be used; use packlist instead.
voidpack_cat(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist, SV ***next_in_list, U32 flags)Return a pointer to the byte-encoded representation of the SV. May cause the SV to be downgraded from UTF-8 as a side-effect.
Usually accessed via theSvPVbyte_nolen macro.
char*sv_2pvbyte_nolen(SV* sv)Return a pointer to the UTF-8-encoded representation of the SV. May cause the SV to be upgraded to UTF-8 as a side-effect.
Usually accessed via theSvPVutf8_nolen macro.
char*sv_2pvutf8_nolen(SV* sv)Likesv_2pv(), but doesn't return the length too. You should usually use the macro wrapperSvPV_nolen(sv) instead. char* sv_2pv_nolen(SV* sv)
Likesv_catpvn, but also handles 'set' magic.
voidsv_catpvn_mg(SV *sv, const char *ptr, STRLEN len)Likesv_catsv, but also handles 'set' magic.
voidsv_catsv_mg(SV *dsv, SV *ssv)Undo 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 an xpvmg. See alsosv_force_normal_flags.
voidsv_force_normal(SV *sv)A private implementation of theSvIVx macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
IVsv_iv(SV* sv)Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test for a NULL function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing().
voidsv_nolocking(SV *sv)Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid test for a NULL function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing().
voidsv_nounlocking(SV *sv)A private implementation of theSvNVx macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
NVsv_nv(SV* sv)Use theSvPV_nolen macro instead
char*sv_pv(SV *sv)UseSvPVbyte_nolen instead.
char*sv_pvbyte(SV *sv)A private implementation of theSvPVbyte macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvbyten(SV *sv, STRLEN *lp)A private implementation of theSvPV macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvn(SV *sv, STRLEN *lp)Use theSvPVutf8_nolen macro instead
char*sv_pvutf8(SV *sv)A private implementation of theSvPVutf8 macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvutf8n(SV *sv, STRLEN *lp)Taint an SV. UseSvTAINTED_on instead. void sv_taint(SV* sv)
Unsets 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. SeeSvROK_off.
voidsv_unref(SV* sv)Tells an SV to useptr to find its string value. Implemented by callingsv_usepvn_flags withflags of 0, hence does not handle 'set' magic. Seesv_usepvn_flags.
voidsv_usepvn(SV* sv, char* ptr, STRLEN len)Likesv_usepvn, but also handles 'set' magic.
voidsv_usepvn_mg(SV *sv, char *ptr, STRLEN len)A private implementation of theSvUVx macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
UVsv_uv(SV* sv)The engine implementing unpack() Perl function. Note: parameters strbeg, new_s and ocnt are not used. This call should not be used, use unpackstring instead.
I32unpack_str(const char *pat, const char *patend, const char *s, const char *strbeg, const char *strend, char **new_s, I32 ocnt, U32 flags)Provides system-specific tune up of the C runtime environment necessary to run Perl interpreters. This should be called only once, before creating any Perl interpreters.
voidPERL_SYS_INIT(int argc, char** argv)Provides system-specific tune up of the C runtime environment necessary to run Perl interpreters. This should be called only once, before creating any Perl interpreters.
voidPERL_SYS_INIT3(int argc, char** argv, char** env)Provides 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.
voidPERL_SYS_TERM()Locate the CV corresponding to the currently executing sub or eval. If db_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. (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)The engine implementing pack() Perl function.
voidpacklist(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist)The engine implementing unpack() Perl function.unpackstring puts the extracted list items on the stack and returns the number of elements. IssuePUTBACK before andSPAGAIN after the call to this function.
I32unpackstring(const char *pat, const char *patend, const char *s, const char *strend, U32 flags)Return the SV from the GV.
SV*GvSV(GV* gv)Ifgv 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, returns NULL.
SV*gv_const_sv(GV* gv)Returns the glob with the givenname and a defined subroutine orNULL. The glob lives in the givenstash, or in the stashes accessible via @ISA and UNIVERSAL::.
The argumentlevel should be either 0 or -1. Iflevel==0, as a side-effect creates a glob with the givenname in the givenstash which in the case of success contains an alias for the subroutine, and sets up caching info for this glob.
This function grants"SUPER" token as a postfix of the stash name. The GV returned fromgv_fetchmeth 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.
GV*gv_fetchmeth(HV* stash, const char* name, STRLEN len, I32 level)Returns 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 via a side effect to do this.
These functions have the same side-effects and asgv_fetchmeth withlevel==0.name should be writable if contains':' or' ''. The warning against passing the GV returned bygv_fetchmeth tocall_sv apply equally to these functions.
GV*gv_fetchmethod_autoload(HV* stash, const char* name, I32 autoload)Same as gv_fetchmeth(), 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.
GV*gv_fetchmeth_autoload(HV* stash, const char* name, STRLEN len, I32 level)Returns 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)Returns 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) then NULL is returned.
HV*gv_stashpvn(const char* name, U32 namelen, I32 flags)Likegv_stashpvn, but takes a literal string instead of a string/length pair.
HV*gv_stashpvs(const char* name, I32 create)Returns a pointer to the stash for a specified package. Seegv_stashpvn.
HV*gv_stashsv(SV* sv, I32 flags)Null AV pointer.
Null character pointer.
Null CV pointer.
Null HV pointer.
Null SV pointer.
Returns 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 and the variable does not exist then NULL is returned.
NOTE: the perl_ form of this function is deprecated.
HV*get_hv(const char *name, I32 flags)This 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).
Returns the computed hash stored in the hash entry.
U32HeHASH(HE* he)Returns 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)If 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.
STRLENHeKLEN(HE* he)Returns 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 alsoHeUTF8.
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)Returns the key as anSV*, orNULL if the hash entry does not contain anSV* key.
SV*HeSVKEY(HE* he)Returns the key as anSV*. Will create and return a temporary mortalSV* if the hash entry contains only achar* key.
SV*HeSVKEY_force(HE* he)Sets 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)Returns 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.
char*HeUTF8(HE* he, STRLEN len)Returns the value slot (typeSV*) stored in the hash entry.
SV*HeVAL(HE* he)Returns the package name of a stash, or NULL ifstash isn't a stash. SeeSvSTASH,CvSTASH.
char*HvNAME(HV* stash)Check that a hash is in an internally consistent state.
voidhv_assert(HV *hv)Clears a hash, making it empty.
voidhv_clear(HV* hv)Clears 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. See Hash::Util::lock_keys() for an example of its use.
voidhv_clear_placeholders(HV *hv)Deletes a key/value pair in the hash. The value SV is removed from the hash and returned to the caller. Theklen is the length of the key. Theflags value will normally be zero; if set to G_DISCARD then NULL will be returned.
SV*hv_delete(HV *hv, const char *key, I32 klen, I32 flags)Deletes a key/value pair in the hash. The value SV is removed from the hash and returned to the caller. Theflags value will normally be zero; if set to G_DISCARD then NULL will be returned.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)Returns a boolean indicating whether the specified hash key exists. Theklen is the length of the key.
boolhv_exists(HV *hv, const char *key, I32 klen)Returns 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.
boolhv_exists_ent(HV *hv, SV *keysv, U32 hash)Returns the SV which corresponds to the specified key in the hash. Theklen is the length of the key. Iflval is set then the fetch will be part of a store. 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)Likehv_fetch, but takes a literal string instead of a string/length pair.
SV**hv_fetchs(HV* tb, const char* key, I32 lval)Returns 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 whentb 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)Prepares a starting point to traverse a hash table. Returns the number of keys in the hash (i.e. the same asHvKEYS(tb)). 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(tb).
I32hv_iterinit(HV *hv)Returns the key from the current position of the hash iterator. Seehv_iterinit.
char*hv_iterkey(HE* entry, I32* retlen)Returns 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 seehv_iterinit.
SV*hv_iterkeysv(HE* entry)Returns entries from a hash iterator. Seehv_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)Performs anhv_iternext,hv_iterkey, andhv_iterval in one operation.
SV*hv_iternextsv(HV *hv, char **key, I32 *retlen)Returns entries from a hash iterator. Seehv_iterinit andhv_iternext. Theflags value will normally be zero; if HV_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&Perl_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.
NOTE: this function is experimental and may change or be removed without notice.
HE*hv_iternext_flags(HV *hv, I32 flags)Returns the value from the current position of the hash iterator. Seehv_iterkey.
SV*hv_iterval(HV *hv, HE *entry)Adds magic to a hash. Seesv_magic.
voidhv_magic(HV *hv, GV *gv, int how)Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
SV*hv_scalar(HV *hv)Stores an SV in a hash. The hash key is specified askey andklen is the length of the key. Thehash parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value will be 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*. 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 successful hv_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 use hv_store in preference to hv_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)Likehv_store, but takes a literal string instead of a string/length pair and omits the hash parameter.
SV**hv_stores(HV* tb, const char* key, NULLOK SV* val)Storesval 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 be 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 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 successful hv_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 that hv_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. 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 use hv_store in preference to hv_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)Undefines the hash.
voidhv_undef(HV *hv)Creates a new HV. The reference count is set to 1.
HV*newHV()Clear something magical that the SV represents. Seesv_magic.
intmg_clear(SV* sv)Copies the magic from one SV to another. Seesv_magic.
intmg_copy(SV *sv, SV *nsv, const char *key, I32 klen)Finds the magic pointer for type matching the SV. Seesv_magic.
MAGIC*mg_find(const SV* sv, int type)Free any magic storage used by the SV. Seesv_magic.
intmg_free(SV* sv)Do magic after a value is retrieved from the SV. Seesv_magic.
intmg_get(SV* sv)Report on the SV's length. Seesv_magic.
U32mg_length(SV* sv)Turns on the magical status of an SV. Seesv_magic.
voidmg_magical(SV* sv)Do magic after a value is assigned to the SV. Seesv_magic.
intmg_set(SV* sv)Invokesmg_get on an SV if it has 'get' magic. This macro evaluates its argument more than once.
voidSvGETMAGIC(SV* sv)Arranges for a mutual exclusion lock to be obtained on sv if a suitable module has been loaded.
voidSvLOCK(SV* sv)Invokesmg_set on an SV if it has 'set' magic. This macro evaluates its argument more than once.
voidSvSETMAGIC(SV* sv)LikeSvSetSV, but does any set magic required afterwards.
voidSvSetMagicSV(SV* dsb, SV* ssv)LikeSvSetSV_nosteal, but does any set magic required afterwards.
voidSvSetMagicSV_nosteal(SV* dsv, SV* ssv)Callssv_setsv if dsv is not the same as ssv. May evaluate arguments more than once.
voidSvSetSV(SV* dsb, SV* ssv)Calls a non-destructive version ofsv_setsv if dsv is not the same as ssv. May evaluate arguments more than once.
voidSvSetSV_nosteal(SV* dsv, SV* ssv)Arranges for sv to be shared between threads if a suitable module has been loaded.
voidSvSHARE(SV* sv)Releases a mutual exclusion lock on sv if a suitable module has been loaded.
voidSvUNLOCK(SV* sv)The 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 alsoMove.
voidCopy(void* src, void* dest, int nitems, type)LikeCopy but returns dest. Useful for encouraging compilers to tail-call optimise.
void *CopyD(void* src, void* dest, int nitems, type)The 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 alsoCopy.
voidMove(void* src, void* dest, int nitems, type)LikeMove but returns dest. Useful for encouraging compilers to tail-call optimise.
void *MoveD(void* src, void* dest, int nitems, type)The XSUB-writer's interface to the Cmalloc function.
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 perlhack). The older API is still there for use in XS modules supporting older perls.
voidNewx(void* ptr, int nitems, type)The XSUB-writer's interface to the Cmalloc function, with cast. See alsoNewx.
voidNewxc(void* ptr, int nitems, type, cast)The XSUB-writer's interface to the Cmalloc function. The allocated memory is zeroed withmemzero. See alsoNewx.
voidNewxz(void* ptr, int nitems, type)PoisonWith(0xEF) for catching access to freed memory.
voidPoison(void* dest, int nitems, type)PoisonWith(0xEF) for catching access to freed memory.
voidPoisonFree(void* dest, int nitems, type)PoisonWith(0xAB) for catching access to allocated but uninitialized memory.
voidPoisonNew(void* dest, int nitems, type)Fill up memory with a byte pattern (a byte repeated over and over again) that hopefully catches attempts to access uninitialized memory.
voidPoisonWith(void* dest, int nitems, type, U8 byte)The XSUB-writer's interface to the Crealloc function.
voidRenew(void* ptr, int nitems, type)The XSUB-writer's interface to the Crealloc function, with cast.
voidRenewc(void* ptr, int nitems, type, cast)The XSUB-writer's interface to the Cfree function.
voidSafefree(void* ptr)Perl's version ofstrdup(). Returns a pointer to a newly allocated string which is a duplicate ofpv. The size of the string is determined bystrlen(). The memory allocated for the new string can be freed with theSafefree() function.
char*savepv(const char* pv)Perl'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 trailing NUL byte. The memory allocated for the new string can be freed with theSafefree() function.
char*savepvn(const char* pv, I32 len)Likesavepvn, but takes a literal string instead of a string/length pair.
char*savepvs(const char* s)A version ofsavepv() which allocates the duplicate string in memory which is shared between threads.
char*savesharedpv(const char* pv)A version ofsavepvn() which allocates the duplicate string in memory which is shared between threads. (With the specific difference that a NULL pointer is not acceptable)
char*savesharedpvn(const char *const pv, const STRLEN len)A version ofsavepv()/savepvn() which gets the string to duplicate from the passed in SV usingSvPV()
char*savesvpv(SV* sv)This is an architecture-independent macro to copy one structure to another.
voidStructCopy(type src, type dest, type)The XSUB-writer's interface to the Cmemzero function. Thedest is the destination,nitems is the number of items, andtype is the type.
voidZero(void* dest, int nitems, type)LikeZero but returns dest. Useful for encouraging compilers to tail-call optimise.
void *ZeroD(void* dest, int nitems, type)Analyses the string in order to make fast searches on it using fbm_instr() -- the Boyer-Moore algorithm.
voidfbm_compile(SV* sv, U32 flags)Returns the location of the SV in the string delimited bystr andstrend. It returnsNULL if the string can't be found. Thesv does not have to be fbm_compiled, but the search will not be as fast then.
char*fbm_instr(unsigned char* big, unsigned char* bigend, SV* littlestr, U32 flags)Takes a sprintf-style format pattern and conventional (non-SV) arguments and returns 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);Uses a single 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).
char*form(const char* pat, ...)Fill the sv with current working directory
intgetcwd_sv(SV* sv)The 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.
intmy_snprintf(char *buffer, const Size_t len, const char *format, ...)The C librarysprintf, wrapped if necessary, to ensure that it will return the length of the string written to the buffer. Only rare pre-ANSI systems need the wrapper function - usually this is a direct call tosprintf.
intmy_sprintf(char *buffer, const char *pat, ...)The C libraryvsnprintf if available and standards-compliant. However, if 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.
intmy_vsnprintf(char *buffer, const Size_t len, const char *format, va_list ap)Returns 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)Returns 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)Test two strings to see if they are equal. Returns true or false.
boolstrEQ(char* s1, char* s2)Test two strings to see if the first,s1, is greater than or equal to the second,s2. Returns true or false.
boolstrGE(char* s1, char* s2)Test two strings to see if the first,s1, is greater than the second,s2. Returns true or false.
boolstrGT(char* s1, char* s2)Test two strings to see if the first,s1, is less than or equal to the second,s2. Returns true or false.
boolstrLE(char* s1, char* s2)Test two strings to see if the first,s1, is less than the second,s2. Returns true or false.
boolstrLT(char* s1, char* s2)Test two strings to see if they are different. Returns true or false.
boolstrNE(char* s1, char* s2)Test two strings to see if they are equal. Thelen parameter indicates the number of bytes to compare. Returns true or false. (A wrapper forstrncmp).
boolstrnEQ(char* s1, char* s2, STRLEN len)Test two strings to see if they are different. Thelen parameter indicates the number of bytes to compare. Returns true or false. (A wrapper forstrncmp).
boolstrnNE(char* s1, char* s2, STRLEN len)Dummy 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 a NULL function pointer and because it could potentially warn under some level of strict-ness.
boolsv_destroyable(SV *sv)Dummy 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 a NULL function pointer and because it could potentially warn under some level of strict-ness.
voidsv_nosharing(SV *sv)In-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)Version object aware cmp. Both operands must already have been converted into version objects.
intvcmp(SV *lhv, SV *rhv)Accepts 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.
SV*vnormal(SV *vs)Accepts 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.
SV*vnumify(SV *vs)In 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
SV*vstringify(SV *vs)Validates that the SV contains a valid version object.
bool vverify(SV *vobj);Note that it only confirms the bare minimum structure (so as not to get confused by derived classes which may contain additional hash entries):
boolvverify(SV *vs)Returns eithermro_get_linear_isa_c3 ormro_get_linear_isa_dfs for the given stash, dependant upon which MRO is in effect for that stash. The return value is a read-only AV*.
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)Invalidates 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 (like constant.pm does).
This same method is available from pure perl via,mro::method_changed_in(classname).
voidmro_method_changed_in(HV* stash)Declare local variables for a multicall. See"Lightweight Callbacks" in perlcall.
dMULTICALL;Make a lightweight callback. See"Lightweight Callbacks" in perlcall.
MULTICALL;Closing bracket for a lightweight callback. See"Lightweight Callbacks" in perlcall.
POP_MULTICALL;Opening bracket for a lightweight callback. See"Lightweight Callbacks" in perlcall.
PUSH_MULTICALL;converts a string representing a binary number to numeric form.
On entrystart and*len give the string to scan,*flags gives conversion flags, andresult should be NULL or a pointer to an NV. The scan stops at the end of the string, or the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT is set in*flags, encountering an invalid character will also trigger a warning. On return*len 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_MAXgrok_bin returns UV_MAX, setsPERL_SCAN_GREATER_THAN_UV_MAX in the output flags, and writes the value to*result (or the value 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 the binary number may use '_' characters to separate digits.
UVgrok_bin(const char* start, STRLEN* len_p, I32* flags, NV *result)converts a string representing a hex number to numeric form.
On entrystart and*len give the string to scan,*flags gives conversion flags, andresult should be NULL or a pointer to an NV. The scan stops at the end of the string, or the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT is set in*flags, encountering an invalid character will also trigger a warning. On return*len 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_MAXgrok_hex returns UV_MAX, setsPERL_SCAN_GREATER_THAN_UV_MAX in the output flags, and writes the value to*result (or the value 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 the hex number may use '_' characters to separate digits.
UVgrok_hex(const char* start, STRLEN* len_p, I32* flags, NV *result)Recognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise it is a bit-ORed combination of IS_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 an in UV, it is returned in the *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 though IS_NUMBER_IN_UV is not set on return. If valuep is NULL, IS_NUMBER_IN_UV will be set for the same cases as when valuep is non-NULL, but no actual assignment (or SEGV) will occur.
IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were seen (in which case *valuep gives the true value truncated to an integer), and IS_NUMBER_NEG if the number is negative (in which case *valuep holds the absolute value). IS_NUMBER_IN_UV is not set if e notation was used or the number is larger than a UV.
intgrok_number(const char *pv, STRLEN len, UV *valuep)Scan and skip for a numeric decimal separator (radix).
boolgrok_numeric_radix(const char **sp, const char *send)converts a string representing an octal number to numeric form.
On entrystart and*len give the string to scan,*flags gives conversion flags, andresult should be NULL or a pointer to an NV. The scan stops at the end of the string, or the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT is set in*flags, encountering an invalid character will also trigger a warning. On return*len 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_MAXgrok_oct returns UV_MAX, setsPERL_SCAN_GREATER_THAN_UV_MAX in the output flags, and writes the value to*result (or the value is discarded ifresult is NULL).
IfPERL_SCAN_ALLOW_UNDERSCORES is set in*flags then the octal number may use '_' characters to separate digits.
UVgrok_oct(const char* start, STRLEN* len_p, I32* flags, NV *result)Return a non-zero integer if the sign bit on an NV is set, and 0 if it is not.
If Configure detects this system has a signbit() that will work with our NVs, then we just use it via the #define in perl.h. Otherwise, fall back on this implementation. As a first pass, this gets everything right except -0.0. Alas, catching -0.0 is the main use for this function, so this is not too helpful yet. Still, at least we have the scaffolding in place to support other systems, should that prove useful.
Configure notes: This function is called 'Perl_signbit' instead of a plain 'signbit' because it is easy to imagine a system having a signbit() function or macro that doesn't happen to work with our particular choice of NVs. We shouldn't just re-#define signbit as Perl_signbit and expect the standard system headers to be happy. Also, this is a no-context function (no pTHX_) because Perl_signbit() is usually re-#defined in perl.h as a simple macro call to the system's signbit(). Users should just always call Perl_signbit().
NOTE: this function is experimental and may change or be removed without notice.
intPerl_signbit(NV f)For backwards compatibility. Usegrok_bin instead.
NVscan_bin(const char* start, STRLEN len, STRLEN* retlen)For backwards compatibility. Usegrok_hex instead.
NVscan_hex(const char* start, STRLEN len, STRLEN* retlen)For backwards compatibility. Usegrok_oct instead.
NVscan_oct(const char* start, STRLEN len, STRLEN* retlen)Ifcv is a constant sub eligible for inlining. returns the constant value returned by the sub. Otherwise, returns NULL.
Constant subs can be created withnewCONSTSUB or as described in"Constant Functions" in perlsub.
SV*cv_const_sv(CV* cv)Creates a constant sub equivalent to Perlsub FOO () { 123 } which is eligible for inlining at compile-time.
CV*newCONSTSUB(HV* stash, const char* name, SV* sv)Used 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.
Get the value at offset po in the current pad. Use macro PAD_SV instead of calling this function directly.
SV*pad_sv(PADOFFSET po)PL_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.
HV*PL_modglobalA convenience variable which is typically used withSvPV when one doesn't care about the length of the string. It is usually more efficient to either declare a local variable and use that instead or to use theSvPV_nolen macro.
STRLENPL_naThis is thefalse SV. SeePL_sv_yes. Always refer to this as&PL_sv_no.
SVPL_sv_noThis is theundef SV. Always refer to this as&PL_sv_undef.
SVPL_sv_undefThis is thetrue SV. SeePL_sv_no. Always refer to this as&PL_sv_yes.
SVPL_sv_yesConvenience 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) && (tmpsv = (SV*)SvRV(sv)) && SvTYPE(tmpsv) == SVt_PVMG && (tmpmg = mg_find(tmpsv, PERL_MAGIC_qr))){ return (REGEXP *)tmpmg->mg_obj;}NULL will be returned if a REGEXP* is not found.
REGEXP *SvRX(SV *sv)Returns a boolean indicating whether the SV contains qr magic (PERL_MAGIC_qr).
If you want to do something with the REGEXP* later use SvRX instead and check for NULL.
boolSvRXOK(SV* sv)Set up necessary local variables for exception handling. See"Exception Handling" in perlguts.
dXCPT;Introduces a catch block. See"Exception Handling" in perlguts.
Rethrows a previously caught exception. See"Exception Handling" in perlguts.
XCPT_RETHROW;Ends a try block. See"Exception Handling" in perlguts.
Starts a try block. See"Exception Handling" in perlguts.
Declare a stack marker variable,mark, for the XSUB. SeeMARK anddORIGMARK.
dMARK;Saves the original stack mark for the XSUB. SeeORIGMARK.
dORIGMARK;Declares a local copy of perl's stack pointer for the XSUB, available via theSP macro. SeeSP.
dSP;Used 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.
voidEXTEND(SP, int nitems)Stack marker variable for the XSUB. SeedMARK.
Push an integer onto the stack. The stack must have room for this element. Does not useTARG. See alsoPUSHi,mXPUSHi andXPUSHi.
voidmPUSHi(IV iv)Push a double onto the stack. The stack must have room for this element. Does not useTARG. See alsoPUSHn,mXPUSHn andXPUSHn.
voidmPUSHn(NV nv)Push a string onto the stack. The stack must have room for this element. Thelen indicates the length of the string. Does not useTARG. See alsoPUSHp,mXPUSHp andXPUSHp.
voidmPUSHp(char* str, STRLEN len)Push an SV onto the stack and mortalizes the SV. The stack must have room for this element. Does not useTARG. See alsoPUSHs andmXPUSHs.
voidmPUSHs(SV* sv)Push an unsigned integer onto the stack. The stack must have room for this element. Does not useTARG. See alsoPUSHu,mXPUSHu andXPUSHu.
voidmPUSHu(UV uv)Push an integer onto the stack, extending the stack if necessary. Does not useTARG. See alsoXPUSHi,mPUSHi andPUSHi.
voidmXPUSHi(IV iv)Push a double onto the stack, extending the stack if necessary. Does not useTARG. See alsoXPUSHn,mPUSHn andPUSHn.
voidmXPUSHn(NV nv)Push a string onto the stack, extending the stack if necessary. Thelen indicates the length of the string. Does not useTARG. See alsoXPUSHp,mPUSHp andPUSHp.
voidmXPUSHp(char* str, STRLEN len)Push an SV onto the stack, extending the stack if necessary and mortalizes the SV. Does not useTARG. See alsoXPUSHs andmPUSHs.
voidmXPUSHs(SV* sv)Push an unsigned integer onto the stack, extending the stack if necessary. Does not useTARG. See alsoXPUSHu,mPUSHu andPUSHu.
voidmXPUSHu(UV uv)The original stack mark for the XSUB. SeedORIGMARK.
Pops an integer off the stack.
IVPOPiPops a long off the stack.
longPOPlPops a double off the stack.
NVPOPnPops a string off the stack. Deprecated. New code should use POPpx.
char*POPpPops a string off the stack which must consist of bytes i.e. characters < 256.
char*POPpbytexPops a string off the stack.
char*POPpxPops an SV off the stack.
SV*POPsPush 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 - seemPUSHi instead. See alsoXPUSHi andmXPUSHi.
voidPUSHi(IV iv)Opening bracket for arguments on a callback. SeePUTBACK andperlcall.
voidPUSHMARK(SP)Push a new mortal SV onto the stack. The stack must have room for this element. Does not useTARG. See alsoPUSHs,XPUSHmortal andXPUSHs.
voidPUSHmortal()Push 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 - seemPUSHn instead. See alsoXPUSHn andmXPUSHn.
voidPUSHn(NV nv)Push 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 - seemPUSHp instead. See alsoXPUSHp andmXPUSHp.
voidPUSHp(char* str, STRLEN len)Push an SV onto the stack. The stack must have room for this element. Does not handle 'set' magic. Does not useTARG. See alsoPUSHmortal,XPUSHs andXPUSHmortal.
voidPUSHs(SV* sv)Push 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 - seemPUSHu instead. See alsoXPUSHu andmXPUSHu.
voidPUSHu(UV uv)Closing bracket for XSUB arguments. This is usually handled byxsubpp. SeePUSHMARK andperlcall for other uses.
PUTBACK;Stack pointer. This is usually handled byxsubpp. SeedSP andSPAGAIN.
Refetch the stack pointer. Used after a callback. Seeperlcall.
SPAGAIN;Push 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 - seemXPUSHi instead. See alsoPUSHi andmPUSHi.
voidXPUSHi(IV iv)Push a new mortal SV onto the stack, extending the stack if necessary. Does not useTARG. See alsoXPUSHs,PUSHmortal andPUSHs.
voidXPUSHmortal()Push 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 - seemXPUSHn instead. See alsoPUSHn andmPUSHn.
voidXPUSHn(NV nv)Push 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 - seemXPUSHp instead. See alsoPUSHp andmPUSHp.
voidXPUSHp(char* str, STRLEN len)Push an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. Does not useTARG. See alsoXPUSHmortal,PUSHs andPUSHmortal.
voidXPUSHs(SV* sv)Push 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 - seemXPUSHu instead. See alsoPUSHu andmPUSHu.
voidXPUSHu(UV uv)Return from XSUB, indicating number of items on the stack. This is usually handled byxsubpp.
voidXSRETURN(int nitems)Return an empty list from an XSUB immediately.
XSRETURN_EMPTY;Return an integer from an XSUB immediately. UsesXST_mIV.
voidXSRETURN_IV(IV iv)Return&PL_sv_no from an XSUB immediately. UsesXST_mNO.
XSRETURN_NO;Return a double from an XSUB immediately. UsesXST_mNV.
voidXSRETURN_NV(NV nv)Return a copy of a string from an XSUB immediately. UsesXST_mPV.
voidXSRETURN_PV(char* str)Return&PL_sv_undef from an XSUB immediately. UsesXST_mUNDEF.
XSRETURN_UNDEF;Return an integer from an XSUB immediately. UsesXST_mUV.
voidXSRETURN_UV(IV uv)Return&PL_sv_yes from an XSUB immediately. UsesXST_mYES.
XSRETURN_YES;Place an integer into the specified positionpos on the stack. The value is stored in a new mortal SV.
voidXST_mIV(int pos, IV iv)Place&PL_sv_no into the specified positionpos on the stack.
voidXST_mNO(int pos)Place a double into the specified positionpos on the stack. The value is stored in a new mortal SV.
voidXST_mNV(int pos, NV nv)Place a copy of a string into the specified positionpos on the stack. The value is stored in a new mortal SV.
voidXST_mPV(int pos, char* str)Place&PL_sv_undef into the specified positionpos on the stack.
voidXST_mUNDEF(int pos)Place&PL_sv_yes into the specified positionpos on the stack.
voidXST_mYES(int pos)An enum of flags for Perl types. These are found in the filesv.h in thesvtype enum. Test these flags with theSvTYPE macro.
Integer type flag for scalars. Seesvtype.
Double type flag for scalars. Seesvtype.
Pointer type flag for scalars. Seesvtype.
Type flag for arrays. Seesvtype.
Type flag for code refs. Seesvtype.
Type flag for hashes. Seesvtype.
Type flag for blessed scalars. Seesvtype.
A 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:
Perl_croak(aTHX_ "Usage %s::%s(%s)", "ouch" "awk", "eee_yow");voidcroak_xs_usage(const CV *const cv, const char *const params)Returns the SV of the specified Perl scalar.flags are passed togv_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: the perl_ form of this function is deprecated.
SV*get_sv(const char *name, I32 flags)Creates an RV wrapper for an SV. The reference count for the original SV is incremented.
SV*newRV_inc(SV* sv)Creates a new SV and copies a string into it. If utf8 is true, callsSvUTF8_on on the new SV. Implemented as a wrapper aroundnewSVpvn_flags.
SV*newSVpvn_utf8(NULLOK const char* s, STRLEN len, U32 utf8)Returns the length of the string which is in the SV. SeeSvLEN.
STRLENSvCUR(SV* sv)Set the current length of the string which is in the SV. SeeSvCUR andSvIV_set.
voidSvCUR_set(SV* sv, STRLEN len)Returns a pointer to the last character in the string which is in the SV. SeeSvCUR. Access the character as *(SvEND(sv)).
char*SvEND(SV* sv)Returns 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.
U32SvGAMAGIC(SV* sv)Expands the character buffer in the SV so that it has room for the indicated number of bytes (remember to reserve space for an extra trailing NUL character). Callssv_grow to perform the expansion if necessary. Returns a pointer to the character buffer.
char *SvGROW(SV* sv, STRLEN len)Returns a U32 value indicating whether the SV contains an integer.
U32SvIOK(SV* sv)Returns a U32 value indicating whether the SV contains an integer. Checks theprivate setting. UseSvIOK instead.
U32SvIOKp(SV* sv)Returns a boolean indicating whether the SV contains a signed integer.
boolSvIOK_notUV(SV* sv)Unsets the IV status of an SV.
voidSvIOK_off(SV* sv)Tells an SV that it is an integer.
voidSvIOK_on(SV* sv)Tells an SV that it is an integer and disables all other OK bits.
voidSvIOK_only(SV* sv)Tells and SV that it is an unsigned integer and disables all other OK bits.
voidSvIOK_only_UV(SV* sv)Returns a boolean indicating whether the SV contains an unsigned integer.
boolSvIOK_UV(SV* sv)Returns a boolean 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)
boolSvIsCOW(SV* sv)Returns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.
boolSvIsCOW_shared_hash(SV* sv)Coerces the given SV to an integer and returns it. SeeSvIVx for a version which guarantees to evaluate sv only once.
IVSvIV(SV* sv)Returns the raw value in the SV's IV slot, without checks or conversions. Only use when you are sure SvIOK is true. See alsoSvIV().
IVSvIVX(SV* sv)Coerces the given SV to an integer and returns it. Guarantees to evaluatesv only once. Only use this ifsv is an expression with side effects, otherwise use the more efficientSvIV.
IVSvIVx(SV* sv)LikeSvIV but doesn't process magic.
IVSvIV_nomg(SV* sv)Set 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.
voidSvIV_set(SV* sv, IV val)Returns the size of the string buffer in the SV, not including any part attributable toSvOOK. SeeSvCUR.
STRLENSvLEN(SV* sv)Set the actual length of the string which is in the SV. SeeSvIV_set.
voidSvLEN_set(SV* sv, STRLEN len)Set the value of the MAGIC pointer in sv to val. SeeSvIV_set.
voidSvMAGIC_set(SV* sv, MAGIC* val)Returns a U32 value indicating whether the SV contains a number, integer or double.
U32SvNIOK(SV* sv)Returns a U32 value indicating whether the SV contains a number, integer or double. Checks theprivate setting. UseSvNIOK instead.
U32SvNIOKp(SV* sv)Unsets the NV/IV status of an SV.
voidSvNIOK_off(SV* sv)Returns a U32 value indicating whether the SV contains a double.
U32SvNOK(SV* sv)Returns a U32 value indicating whether the SV contains a double. Checks theprivate setting. UseSvNOK instead.
U32SvNOKp(SV* sv)Unsets the NV status of an SV.
voidSvNOK_off(SV* sv)Tells an SV that it is a double.
voidSvNOK_on(SV* sv)Tells an SV that it is a double and disables all other OK bits.
voidSvNOK_only(SV* sv)Coerce the given SV to a double and return it. SeeSvNVx for a version which guarantees to evaluate sv only once.
NVSvNV(SV* sv)Returns the raw value in the SV's NV slot, without checks or conversions. Only use when you are sure SvNOK is true. See alsoSvNV().
NVSvNVX(SV* sv)Coerces the given SV to a double and returns it. Guarantees to evaluatesv only once. Only use this ifsv is an expression with side effects, otherwise use the more efficientSvNV.
NVSvNVx(SV* sv)Set the value of the NV pointer in sv to val. SeeSvIV_set.
voidSvNV_set(SV* sv, NV val)Returns a U32 value indicating whether the value is defined. This is only meaningful for scalars.
U32SvOK(SV* sv)Returns a U32 indicating whether the SvIVX is a valid offset value for the SvPVX. This hack is used internally to speed up removal of characters from the beginning of a SvPV. When SvOOK is true, then the start of the allocated string buffer is really (SvPVX - SvIVX).
U32SvOOK(SV* sv)Returns a U32 value indicating whether the SV contains a character string.
U32SvPOK(SV* sv)Returns a U32 value indicating whether the SV contains a character string. Checks theprivate setting. UseSvPOK instead.
U32SvPOKp(SV* sv)Unsets the PV status of an SV.
voidSvPOK_off(SV* sv)Tells an SV that it is a string.
voidSvPOK_on(SV* sv)Tells an SV that it is a string and disables all other OK bits. Will also turn off the UTF-8 status.
voidSvPOK_only(SV* sv)Tells an SV that it is a string and disables all other OK bits, and leaves the UTF-8 status as it was.
voidSvPOK_only_UTF8(SV* sv)Returns a pointer to the string in the SV, or a stringified form of the SV if the SV does not contain a string. The SV may cache the stringified version becomingSvPOK. Handles 'get' magic. See alsoSvPVx for a version which guarantees to evaluate sv only once.
char*SvPV(SV* sv, STRLEN len)LikeSvPV, but converts sv to byte representation first if necessary.
char*SvPVbyte(SV* sv, STRLEN len)LikeSvPV, but converts sv to byte representation first if necessary. Guarantees to evaluate sv only once; use the more efficientSvPVbyte otherwise.
char*SvPVbytex(SV* sv, STRLEN len)LikeSvPV_force, but converts sv to byte representation first if necessary. Guarantees to evaluate sv only once; use the more efficientSvPVbyte_force otherwise.
char*SvPVbytex_force(SV* sv, STRLEN len)LikeSvPV_force, but converts sv to byte representation first if necessary.
char*SvPVbyte_force(SV* sv, STRLEN len)LikeSvPV_nolen, but converts sv to byte representation first if necessary.
char*SvPVbyte_nolen(SV* sv)LikeSvPV, but converts sv to utf8 first if necessary.
char*SvPVutf8(SV* sv, STRLEN len)LikeSvPV, but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once; use the more efficientSvPVutf8 otherwise.
char*SvPVutf8x(SV* sv, STRLEN len)LikeSvPV_force, but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once; use the more efficientSvPVutf8_force otherwise.
char*SvPVutf8x_force(SV* sv, STRLEN len)LikeSvPV_force, but converts sv to utf8 first if necessary.
char*SvPVutf8_force(SV* sv, STRLEN len)LikeSvPV_nolen, but converts sv to utf8 first if necessary.
char*SvPVutf8_nolen(SV* sv)Returns a pointer to the physical string in the SV. The SV must contain a string.
char*SvPVX(SV* sv)A version ofSvPV which guarantees to evaluatesv only once. Only use this ifsv is an expression with side effects, otherwise use the more efficientSvPVX.
char*SvPVx(SV* sv, STRLEN len)LikeSvPV but will force the SV into containing just a string (SvPOK_only). You want force if you are going to update theSvPVX directly.
char*SvPV_force(SV* sv, STRLEN len)LikeSvPV but will force the SV into containing just a string (SvPOK_only). You want force if you are going to update theSvPVX directly. Doesn't process magic.
char*SvPV_force_nomg(SV* sv, STRLEN len)Returns a pointer to the string in the SV, or a stringified form of the SV if the SV does not contain a string. The SV may cache the stringified form becomingSvPOK. Handles 'get' magic.
char*SvPV_nolen(SV* sv)LikeSvPV but doesn't process magic.
char*SvPV_nomg(SV* sv, STRLEN len)Set the value of the PV pointer in sv to val. SeeSvIV_set.
voidSvPV_set(SV* sv, char* val)Returns the value of the object's reference count.
U32SvREFCNT(SV* sv)Decrements the reference count of the given SV.
voidSvREFCNT_dec(SV* sv)Increments the reference count of the given SV.
All of the following SvREFCNT_inc* macros are optimized versions of SvREFCNT_inc, and can be replaced with SvREFCNT_inc.
SV*SvREFCNT_inc(SV* sv)Same as SvREFCNT_inc, but can only be used if you knowsv is not NULL. Since we don't have to check the NULLness, it's faster and smaller.
SV*SvREFCNT_inc_NN(SV* sv)Same as SvREFCNT_inc, but can only be used with expressions without side effects. Since we don't have to store a temporary value, it's faster.
SV*SvREFCNT_inc_simple(SV* sv)Same as SvREFCNT_inc_simple, but can only be used if you knowsv is not NULL. Since we don't have to check the NULLness, it's faster and smaller.
SV*SvREFCNT_inc_simple_NN(SV* sv)Same as SvREFCNT_inc_simple, but can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
voidSvREFCNT_inc_simple_void(SV* sv)Same as SvREFCNT_inc, but can only be used if you don't need the return value, and you know thatsv is not NULL. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
voidSvREFCNT_inc_simple_void_NN(SV* sv)Same as SvREFCNT_inc, but can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
voidSvREFCNT_inc_void(SV* sv)Same as SvREFCNT_inc, but can only be used if you don't need the return value, and you know thatsv is not NULL. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
voidSvREFCNT_inc_void_NN(SV* sv)Tests if the SV is an RV.
U32SvROK(SV* sv)Unsets the RV status of an SV.
voidSvROK_off(SV* sv)Tells an SV that it is an RV.
voidSvROK_on(SV* sv)Dereferences an RV to return the SV.
SV*SvRV(SV* sv)Set the value of the RV pointer in sv to val. SeeSvIV_set.
voidSvRV_set(SV* sv, SV* val)Returns the stash of the SV.
HV*SvSTASH(SV* sv)Set the value of the STASH pointer in sv to val. SeeSvIV_set.
voidSvSTASH_set(SV* sv, HV* val)Taints an SV if tainting is enabled.
voidSvTAINT(SV* sv)Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.
boolSvTAINTED(SV* sv)Untaints 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.
voidSvTAINTED_off(SV* sv)Marks an SV as tainted if tainting is enabled.
voidSvTAINTED_on(SV* sv)Returns a boolean indicating whether Perl would evaluate the SV as true or false. See SvOK() for a defined/undefined test. Does not handle 'get' magic.
boolSvTRUE(SV* sv)Returns the type of the SV. Seesvtype.
svtypeSvTYPE(SV* sv)Returns a boolean indicating whether the SV contains an unsigned integer.
boolSvUOK(SV* sv)Used to upgrade an SV to a more complex form. Usessv_upgrade to perform the upgrade if necessary. Seesvtype.
voidSvUPGRADE(SV* sv, svtype type)Returns a U32 value indicating whether the SV contains UTF-8 encoded data. Call this after SvPV() in case any call to string overloading updates the internal flag.
U32SvUTF8(SV* sv)Unsets the UTF-8 status of an SV.
voidSvUTF8_off(SV *sv)Turn on the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
voidSvUTF8_on(SV *sv)Coerces the given SV to an unsigned integer and returns it. SeeSvUVx for a version which guarantees to evaluate sv only once.
UVSvUV(SV* sv)Returns the raw value in the SV's UV slot, without checks or conversions. Only use when you are sure SvIOK is true. See alsoSvUV().
UVSvUVX(SV* sv)Coerces the given SV to an unsigned integer and returns it. Guarantees tosv only once. Only use this ifsv is an expression with side effects, otherwise use the more efficientSvUV.
UVSvUVx(SV* sv)LikeSvUV but doesn't process magic.
UVSvUV_nomg(SV* sv)Set the value of the UV pointer in sv to val. SeeSvIV_set.
voidSvUV_set(SV* sv, UV val)Returns a boolean indicating whether the SV contains a v-string.
boolSvVOK(SV* sv)Likesv_catpvn but doesn't process magic.
voidsv_catpvn_nomg(SV* sv, const char* ptr, STRLEN len)Likesv_catsv but doesn't process magic.
voidsv_catsv_nomg(SV* dsv, SV* ssv)Returns 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.
boolsv_derived_from(SV* sv, const char* name)Returns 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.
boolsv_does(SV* sv, const char* name)Dump the contents of all SVs not yet freed. (Debugging aid).
voidsv_report_used()Likesv_setsv but doesn't process magic.
voidsv_setsv_nomg(SV* dsv, SV* ssv)Like sv_utf8_upgrade, but doesn't do magic onsv
STRLENsv_utf8_upgrade_nomg(NN SV *sv)Test 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 your atof() doesn't grok them.
I32looks_like_number(SV* sv)Creates an RV wrapper for an SV. The reference count for the original SV isnot incremented.
SV*newRV_noinc(SV* sv)Creates 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 trailing NUL 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 older NEWSV() 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 perlhack). The older API is still there for use in XS modules supporting older perls.
SV*newSV(STRLEN len)Creates 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 if the hek is NULL.
SV*newSVhek(const HEK *hek)Creates a new SV and copies an integer into it. The reference count for the SV is set to 1.
SV*newSViv(IV i)Creates a new SV and copies a floating point value into it. The reference count for the SV is set to 1.
SV*newSVnv(NV n)Creates a new SV and copies a string into it. The reference count for the SV is set to 1. Iflen is zero, Perl will compute the length using strlen(). For efficiency, consider usingnewSVpvn instead.
SV*newSVpv(const char* s, STRLEN len)Creates a new SV and initializes it with the string formatted likesprintf.
SV*newSVpvf(const char* pat, ...)Creates a new SV and copies a string 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.
SV*newSVpvn(const char* s, STRLEN len)Creates a new SV and copies a string 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, thensv2mortal() is called on the result before returning. IfSVf_UTF8 is set, then it 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* s, STRLEN len, U32 flags)Creates a new SV with its SvPVX_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 READONLY and FAKE. If thehash parameter is non-zero, that value is used; otherwise the hash is computed. The string's hash can be later be retrieved from the SV with theSvSHARED_HASH() macro. The idea here is that as the string table is used for shared hash keys these strings will have SvPVX_const == HeKEY and hash lookup will avoid string compare.
SV*newSVpvn_share(const char* s, I32 len, U32 hash)LikenewSVpvn, but takes a literal string instead of a string/length pair.
SV*newSVpvs(const char* s)LikenewSVpvn_flags, but takes a literal string instead of a string/length pair.
SV*newSVpvs_flags(const char* s, U32 flags)LikenewSVpvn_share, but takes a literal string instead of a string/length pair and omits the hash parameter.
SV*newSVpvs_share(const char* s)Creates a new SV for the 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.
SV*newSVrv(SV* rv, const char* classname)Creates a new SV which is an exact duplicate of the original SV. (Usessv_setsv).
SV*newSVsv(SV* old)Creates a new SV and copies an unsigned integer into it. The reference count for the SV is set to 1.
SV*newSVuv(UV u)Creates a new SV, of the type specified. The reference count for the new SV is set to 1.
SV*newSV_type(svtype type)This function is only called on magical items, and is only used by sv_true() or its macro equivalent.
boolsv_2bool(SV* sv)Using 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 to sv_fetchsv.
CV*sv_2cv(SV* sv, HV** st, GV** gvp, I32 lref)Using 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.
IO*sv_2io(SV* sv)Return the integer value of an SV, doing any necessary string conversion. If flags includes SV_GMAGIC, does an mg_get() first. Normally used via theSvIV(sv) andSvIVx(sv) macros.
IVsv_2iv_flags(SV* sv, I32 flags)Marks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call to FREETMPS, 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 alsosv_newmortal andsv_mortalcopy.
SV*sv_2mortal(SV* sv)Return the num value of an SV, doing any necessary string or integer conversion, magic etc. Normally used via theSvNV(sv) andSvNVx(sv) macros.
NVsv_2nv(SV* sv)Return a pointer to the byte-encoded representation of the SV, and set *lp to its length. May cause the SV to be downgraded from UTF-8 as a side-effect.
Usually accessed via theSvPVbyte macro.
char*sv_2pvbyte(SV* sv, STRLEN* lp)Return a pointer to the UTF-8-encoded representation of the SV, and set *lp to its length. May cause the SV to be upgraded to UTF-8 as a side-effect.
Usually accessed via theSvPVutf8 macro.
char*sv_2pvutf8(SV* sv, STRLEN* lp)Returns a pointer to the string value of an SV, and sets *lp to its length. If flags includes SV_GMAGIC, does an mg_get() first. Coerces sv to a string if necessary. Normally invoked via theSvPV_flags macro.sv_2pv() andsv_2pv_nomg usually end up here too.
char*sv_2pv_flags(SV* sv, STRLEN* lp, I32 flags)Return the unsigned integer value of an SV, doing any necessary string conversion. If flags includes SV_GMAGIC, does an mg_get() first. Normally used via theSvUV(sv) andSvUVx(sv) macros.
UVsv_2uv_flags(SV* sv, I32 flags)Remove any string offset. You should normally use theSvOOK_off macro wrapper instead.
intsv_backoff(SV* sv)Blesses an SV into a specified package. The SV must be an RV. The package must be designated by its stash (seegv_stashpv()). The reference count of the SV is unaffected.
SV*sv_bless(SV* sv, HV* stash)Concatenates the string 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. Handles 'get' magic, but not 'set' magic. Seesv_catpv_mg.
voidsv_catpv(SV* sv, const char* ptr)Processes its arguments likesprintf and appends the formatted output to an SV. 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. Handles 'get' magic, but not 'set' magic. Seesv_catpvf_mg. 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.
voidsv_catpvf(SV* sv, const char* pat, ...)Likesv_catpvf, but also handles 'set' magic.
voidsv_catpvf_mg(SV *sv, const char* pat, ...)Concatenates the string onto the end of the string which is in the SV. Thelen indicates number of bytes to copy. If the SV has the UTF-8 status set, then the bytes appended should be valid UTF-8. Handles 'get' magic, but not 'set' magic. Seesv_catpvn_mg.
voidsv_catpvn(SV *dsv, const char *sstr, STRLEN len)Concatenates the string onto the end of the string which is in the SV. Thelen indicates number of bytes to copy. If the SV has the UTF-8 status set, then the bytes appended should be valid UTF-8. Ifflags hasSV_GMAGIC bit set, willmg_get ondsv if appropriate, else not.sv_catpvn andsv_catpvn_nomg are implemented in terms of this function.
voidsv_catpvn_flags(SV *dstr, const char *sstr, STRLEN len, I32 flags)Likesv_catpvn, but takes a literal string instead of a string/length pair.
voidsv_catpvs(SV* sv, const char* s)Likesv_catpv, but also handles 'set' magic.
voidsv_catpv_mg(SV *sv, const char *ptr)Concatenates the string from SVssv onto the end of the string in SVdsv. Modifiesdsv but notssv. Handles 'get' magic, but not 'set' magic. Seesv_catsv_mg.
voidsv_catsv(SV *dstr, SV *sstr)Concatenates the string from SVssv onto the end of the string in SVdsv. Modifiesdsv but notssv. Ifflags hasSV_GMAGIC bit set, willmg_get on the SVs if appropriate, else not.sv_catsv andsv_catsv_nomg are implemented in terms of this function.
voidsv_catsv_flags(SV* dsv, SV* ssv, I32 flags)Efficient removal of characters from the beginning of the string buffer. SvPOK(sv) must be true and theptr must be a pointer to somewhere inside the string buffer. Theptr becomes the first character of the adjusted string. Uses the "OOK hack". Beware: after this function returns,ptr and SvPVX_const(sv) may no longer refer to the same chunk of data.
voidsv_chop(SV* sv, const char* ptr)Clear 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 when REFCNT is zero. Most of the time you'll want to callsv_free() (or its macro wrapperSvREFCNT_dec) instead.
voidsv_clear(SV* sv)Compares 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 alsosv_cmp_locale.
I32sv_cmp(SV* sv1, SV* sv2)Compares 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 alsosv_cmp.
I32sv_cmp_locale(SV* sv1, SV* sv2)Add Collate Transform magic to an SV if it doesn't already have it.
Any scalar variable may carry PERL_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(SV* sv, STRLEN* nxp)Copies a stringified representation of the source SV into the destination SV. Automatically performs any necessary mg_get and coercion of numeric values into strings. Guaranteed to preserve UTF8 flag even from overloaded objects. Similar in nature to sv_2pv[_flags] but operates directly on an SV instead of just the string. Mostly uses sv_2pv_flags to do its work, except when that would lose the UTF-8'ness of the PV.
voidsv_copypv(SV* dsv, SV* ssv)Auto-decrement of the value in the SV, doing string to numeric conversion if necessary. Handles 'get' magic.
voidsv_dec(SV* sv)Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF-8 and 'use bytes' aware, handles get magic, and will coerce its args to strings if necessary.
I32sv_eq(SV* sv1, SV* sv2)Undo 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 an xpvmg; if we're a copy-on-write scalar, this is the on-write time when we do the copy, and is also used locally. IfSV_COW_DROP_PV is set then a copy-on-write scalar drops its PV buffer (if any) and becomes SvPOK_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 unrefing.sv_force_normal calls this function with flags set to 0.
voidsv_force_normal_flags(SV *sv, U32 flags)Decrement 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, deallocate the SV's head itself. Normally called via a wrapper macroSvREFCNT_dec.
voidsv_free(SV* sv)Get a line from the filehandle and store it into the SV, optionally appending to the currently-stored string.
char*sv_gets(SV* sv, PerlIO* fp, I32 append)Expands the character buffer in the SV. If necessary, usessv_unref and upgrades the SV toSVt_PV. Returns a pointer to the character buffer. Use theSvGROW wrapper instead.
char*sv_grow(SV* sv, STRLEN newlen)Auto-increment of the value in the SV, doing string to numeric conversion if necessary. Handles 'get' magic.
voidsv_inc(SV* sv)Inserts a string at the specified offset/length within the SV. Similar to the Perl substr() function. Handles get magic.
voidsv_insert(SV *bigstr, STRLEN offset, STRLEN len, const char *little, STRLEN littlelen)Same assv_insert, but the extraflags are passed theSvPV_force_flags that applies tobigstr.
voidsv_insert_flags(SV *const bigstr, const STRLEN offset, const STRLEN len, const char *const little, const STRLEN littlelen, const U32 flags)Returns a boolean indicating whether the SV is blessed into the specified class. This does not check for subtypes; usesv_derived_from to verify an inheritance relationship.
intsv_isa(SV* sv, const char* name)Returns 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.
intsv_isobject(SV* sv)Returns the length of the string in the SV. Handles magic and type coercion. See alsoSvCUR, which gives raw access to the xpv_cur slot.
STRLENsv_len(SV* sv)Returns the number of characters in the string in an SV, counting wide UTF-8 bytes as a single character. Handles magic and type coercion.
STRLENsv_len_utf8(SV* sv)Adds 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.
Seesv_magicext (whichsv_magic now calls) for a description of the handling of thename andnamlen arguments.
You need to usesv_magicext to add magic to SvREADONLY SVs and also to add more than one instance of the same 'how'.
voidsv_magic(SV* sv, SV* obj, int how, const char* name, I32 namlen)Adds magic to an SV, upgrading it if necessary. Applies the supplied vtable and returns a pointer to the magic added.
Note thatsv_magicext will allow things thatsv_magic will not. In particular, you can add magic to SvREADONLY SVs, and add more than one instance of the same 'how'.
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 anSV* and is stored as-is with its REFCNT incremented.
(This is now used as a subroutine bysv_magic.)
MAGIC *sv_magicext(SV* sv, SV* obj, int how, const MGVTBL *vtbl, const char* name, I32 namlen)Creates 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 to FREETMPS, or by an implicit call at places such as statement boundaries. See alsosv_newmortal andsv_2mortal.
SV*sv_mortalcopy(SV* oldsv)Creates 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 to FREETMPS, or by an implicit call at places such as statement boundaries. See alsosv_mortalcopy andsv_2mortal.
SV*sv_newmortal()Increment an SV's reference count. Use theSvREFCNT_inc() wrapper instead.
SV*sv_newref(SV* sv)Converts the value pointed to by offsetp 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.
voidsv_pos_b2u(SV* sv, I32* offsetp)Converts the value pointed to by offsetp from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; if lenp is non-zero, it does the same to lenp, but this time starting from the offset, rather than from the start of the string. Handles magic and type coercion.
voidsv_pos_u2b(SV* sv, I32* offsetp, I32* lenp)The backend for theSvPVbytex_force macro. Always use the macro instead.
char*sv_pvbyten_force(SV* sv, STRLEN* lp)Get a sensible string out of the SV somehow. A private implementation of theSvPV_force macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvn_force(SV* sv, STRLEN* lp)Get a sensible string out of the SV somehow. Ifflags hasSV_GMAGIC bit set, willmg_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: seeSvPV_force andSvPV_force_nomg
char*sv_pvn_force_flags(SV* sv, STRLEN* lp, I32 flags)The backend for theSvPVutf8x_force macro. Always use the macro instead.
char*sv_pvutf8n_force(SV* sv, STRLEN* lp)Returns a string describing what the SV is a reference to.
const char*sv_reftype(const SV* sv, int ob)Make 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.
voidsv_replace(SV* sv, SV* nsv)Underlying implementation for thereset Perl function. Note that the perl-level function is vaguely deprecated.
voidsv_reset(const char* s, HV* stash)Weaken 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.
SV*sv_rvweaken(SV *sv)Copies an integer into the given SV, upgrading first if necessary. Does not handle 'set' magic. See alsosv_setiv_mg.
voidsv_setiv(SV* sv, IV num)Likesv_setiv, but also handles 'set' magic.
voidsv_setiv_mg(SV *sv, IV i)Copies a double into the given SV, upgrading first if necessary. Does not handle 'set' magic. See alsosv_setnv_mg.
voidsv_setnv(SV* sv, NV num)Likesv_setnv, but also handles 'set' magic.
voidsv_setnv_mg(SV *sv, NV num)Copies a string into an SV. The string must be null-terminated. Does not handle 'set' magic. Seesv_setpv_mg.
voidsv_setpv(SV* sv, const char* ptr)Works likesv_catpvf but copies the text into the SV instead of appending it. Does not handle 'set' magic. Seesv_setpvf_mg.
voidsv_setpvf(SV* sv, const char* pat, ...)Likesv_setpvf, but also handles 'set' magic.
voidsv_setpvf_mg(SV *sv, const char* pat, ...)Copies an integer into the given SV, also updating its string value. Does not handle 'set' magic. Seesv_setpviv_mg.
voidsv_setpviv(SV* sv, IV num)Likesv_setpviv, but also handles 'set' magic.
voidsv_setpviv_mg(SV *sv, IV iv)Copies a string into an SV. Thelen parameter indicates the number of bytes to be copied. If theptr argument is NULL the SV will become undefined. Does not handle 'set' magic. Seesv_setpvn_mg.
voidsv_setpvn(SV* sv, const char* ptr, STRLEN len)Likesv_setpvn, but also handles 'set' magic.
voidsv_setpvn_mg(SV *sv, const char *ptr, STRLEN len)Likesv_setpvn, but takes a literal string instead of a string/length pair.
voidsv_setpvs(SV* sv, const char* s)Likesv_setpv, but also handles 'set' magic.
voidsv_setpv_mg(SV *sv, const char *ptr)Copies 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* rv, const char* classname, IV iv)Copies 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* rv, const char* classname, NV nv)Copies 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 is NULL 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* rv, const char* classname, void* pv)Copies 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* rv, const char* classname, const char* pv, STRLEN n)Copies 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* rv, const char* classname, UV uv)Copies the contents of the source SVssv into the destination SVdsv. The source SV may be destroyed if it is mortal, so don't use this function if the source SV needs to be reused. Does not handle 'set' magic. Loosely speaking, it performs a copy-by-value, obliterating any previous content of the destination.
You probably want to use one of the assortment of wrappers, such asSvSetSV,SvSetSV_nosteal,SvSetMagicSV andSvSetMagicSV_nosteal.
voidsv_setsv(SV *dstr, SV *sstr)Copies the contents of the source SVssv into the destination SVdsv. The source SV may be destroyed if it is mortal, so don't use this function if the source SV needs to be reused. Does not handle 'set' magic. Loosely speaking, it performs a copy-by-value, obliterating any previous content of the destination. If theflags parameter has theSV_GMAGIC bit set, willmg_get onssv if appropriate, else not. If theflags parameter has theNOSTEAL bit set then the buffers of temps will not be stolen. <sv_setsv> andsv_setsv_nomg are implemented in terms of this function.
You probably want to use one of the assortment of wrappers, such asSvSetSV,SvSetSV_nosteal,SvSetMagicSV andSvSetMagicSV_nosteal.
This is the primary function for copying scalars, and most other copy-ish functions and macros use this underneath.
voidsv_setsv_flags(SV *dstr, SV *sstr, I32 flags)Likesv_setsv, but also handles 'set' magic.
voidsv_setsv_mg(SV *dstr, SV *sstr)Copies an unsigned integer into the given SV, upgrading first if necessary. Does not handle 'set' magic. See alsosv_setuv_mg.
voidsv_setuv(SV* sv, UV num)Likesv_setuv, but also handles 'set' magic.
voidsv_setuv_mg(SV *sv, UV u)Test an SV for taintedness. UseSvTAINTED instead. bool sv_tainted(SV* sv)
Returns true if the SV has a true value by Perl's rules. Use theSvTRUE macro instead, which may callsv_true() or may instead use an in-line version.
I32sv_true(SV *sv)Removes all magic of typetype from an SV.
intsv_unmagic(SV* sv, int type)Unsets 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). SeeSvROK_off.
voidsv_unref_flags(SV *ref, U32 flags)Untaint an SV. UseSvTAINTED_off instead. void sv_untaint(SV* sv)
Upgrade 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. You generally want to use theSvUPGRADE macro wrapper. See alsosvtype.
voidsv_upgrade(SV* sv, svtype new_type)Tells an SV to useptr to find its string value. Normally the string is stored inside the SV but sv_usepvn allows the SV to use an outside string. Theptr should point to memory that was allocated bymalloc. The string length,len, must be supplied. By default this function will realloc (i.e. move) the memory pointed to byptr, so that pointer should not be freed or used by the programmer after giving it to sv_usepvn, and neither should any pointers from "behind" that pointer (e.g. ptr + 1) be used.
Ifflags & SV_SMAGIC is true, will call SvSETMAGIC. Ifflags & SV_HAS_TRAILING_NUL is true, thenptr[len] must be NUL, 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)
voidsv_usepvn_flags(SV* sv, char* ptr, STRLEN len, U32 flags)If the PV of the SV is an octet sequence in 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 being off. Scans PV for validity and returns false if the PV is invalid UTF-8.
NOTE: this function is experimental and may change or be removed without notice.
boolsv_utf8_decode(SV *sv)Attempts 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, either returns false or, iffail_ok is not true, croaks.
This is not as a general purpose Unicode to byte encoding interface: use the Encode extension for that.
NOTE: this function is experimental and may change or be removed without notice.
boolsv_utf8_downgrade(SV *sv, bool fail_ok)Converts the PV of an SV to UTF-8, but then turns theSvUTF8 flag off so that it looks like octets again.
voidsv_utf8_encode(SV *sv)Converts the PV of an SV to its UTF-8-encoded form. Forces the SV to string form if it is not already. Willmg_get onsv if appropriate. Always sets the SvUTF8 flag to avoid future validity checks even if the whole string is the same in UTF-8 as not. Returns the number of bytes in the converted string
This is not as a general purpose byte encoding to Unicode interface: use the Encode extension for that.
STRLENsv_utf8_upgrade(SV *sv)Converts the PV of an SV to its UTF-8-encoded form. Forces the SV to string form if it is not already. Always sets the SvUTF8 flag to avoid future validity checks even if all the bytes are invariant in UTF-8. Ifflags hasSV_GMAGIC bit set, willmg_get onsv if appropriate, else not. Returns the number of bytes in the converted stringsv_utf8_upgrade andsv_utf8_upgrade_nomg are implemented in terms of this function.
This is not as a general purpose byte encoding to Unicode interface: use the Encode extension for that.
STRLENsv_utf8_upgrade_flags(SV *sv, I32 flags)Like sv_utf8_upgrade, but doesn't do magic onsv
STRLENsv_utf8_upgrade_nomg(SV *sv)Processes its arguments likevsprintf and appends the formatted output to an SV. Does not handle 'set' magic. Seesv_vcatpvf_mg.
Usually used via its frontendsv_catpvf.
voidsv_vcatpvf(SV* sv, const char* pat, va_list* args)Processes its arguments likevsprintf and appends the formatted output to an SV. Uses an array of SVs if the C style variable argument list is missing (NULL). When running with taint checks enabled, indicates viamaybe_tainted if results are untrustworthy (often due to the use of locales).
Usually used via one of its frontendssv_vcatpvf andsv_vcatpvf_mg.
voidsv_vcatpvfn(SV* sv, const char* pat, STRLEN patlen, va_list* args, SV** svargs, I32 svmax, bool *maybe_tainted)Likesv_vcatpvf, but also handles 'set' magic.
Usually used via its frontendsv_catpvf_mg.
voidsv_vcatpvf_mg(SV* sv, const char* pat, va_list* args)Works likesv_vcatpvf but copies the text into the SV instead of appending it. Does not handle 'set' magic. Seesv_vsetpvf_mg.
Usually used via its frontendsv_setpvf.
voidsv_vsetpvf(SV* sv, const char* pat, va_list* args)Works likesv_vcatpvfn but copies the text into the SV instead of appending it.
Usually used via one of its frontendssv_vsetpvf andsv_vsetpvf_mg.
voidsv_vsetpvfn(SV* sv, const char* pat, STRLEN patlen, va_list* args, SV** svargs, I32 svmax, bool *maybe_tainted)Likesv_vsetpvf, but also handles 'set' magic.
Usually used via its frontendsv_setpvf_mg.
voidsv_vsetpvf_mg(SV* sv, const char* pat, va_list* args)Converts a strings of lengthlen from UTF-8 into native byte encoding. Unlikeutf8_to_bytes but likebytes_to_utf8, returns a pointer to the newly-created string, and updateslen to contain the new length. Returns the original string if no conversion occurs,len is unchanged. Do nothing ifis_utf8 points to 0. Setsis_utf8 to 0 ifs is converted or consisted entirely of characters that are invariant in utf8 (i.e., US-ASCII on non-EBCDIC machines).
NOTE: this function is experimental and may change or be removed without notice.
U8*bytes_from_utf8(const U8 *s, STRLEN *len, bool *is_utf8)Converts a strings of lengthlen from the native encoding into UTF-8. Returns a pointer to the newly-created string, and setslen to reflect the new length.
A NUL 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().
NOTE: this function is experimental and may change or be removed without notice.
U8*bytes_to_utf8(const U8 *s, STRLEN *len)Return true if the strings s1 and s2 differ case-insensitively, false if not (if they are equal case-insensitively). If u1 is true, the string s1 is assumed to be in UTF-8-encoded Unicode. If u2 is true, the string s2 is assumed to be in UTF-8-encoded Unicode. If u1 or u2 are false, the respective string is assumed to be in native 8-bit encoding.
If the pe1 and pe2 are non-NULL, the scanning pointers will be copied in there (they will point at the beginning of thenext character). If the pointers behind pe1 or pe2 are non-NULL, they are the end pointers beyond which scanning will not continue under any circumstances. If the byte lengths l1 and l2 are non-zero, s1+l1 and s2+l2 will be used as goal end pointers that will also stop the scan, and which qualify towards defining a successful match: all the scans that define an explicit length must reach their goal pointers for a match to succeed).
For case-insensitiveness, the "casefolding" of Unicode is used instead of upper/lowercasing both the characters, see http://www.unicode.org/unicode/reports/tr21/ (Case Mappings).
I32ibcmp_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)Tests if some arbitrary number of bytes begins in a valid UTF-8 character. Note that an INVARIANT (i.e. ASCII on non-EBCDIC machines) character is a valid UTF-8 character. The actual number of bytes in the UTF-8 character will be returned if it is valid, otherwise 0.
STRLENis_utf8_char(const U8 *s)Returns true if firstlen bytes of the given string form a valid UTF-8 string, false otherwise. Note that 'a valid UTF-8 string' does not mean 'a string that contains code points above 0x7F encoded in UTF-8' because a valid ASCII string is a valid UTF-8 string.
See also is_utf8_string_loclen() and is_utf8_string_loc().
boolis_utf8_string(const U8 *s, STRLEN len)Like is_utf8_string() but stores the location of the failure (in the case of "utf8ness failure") or the location s+len (in the case of "utf8ness success") in theep.
See also is_utf8_string_loclen() and is_utf8_string().
boolis_utf8_string_loc(const U8 *s, STRLEN len, const U8 **p)Like is_utf8_string() but stores the location of the failure (in the case of "utf8ness failure") or the location s+len (in the case of "utf8ness success") in theep, and the number of UTF-8 encoded characters in theel.
See also is_utf8_string_loc() and is_utf8_string().
boolis_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)Build to the scalar dsv a displayable version of the string spv, length len, the displayable version being at most pvlim bytes long (if longer, the rest is truncated and "..." will be appended).
The flags argument can have UNI_DISPLAY_ISPRINT set to display isPRINT()able characters as themselves, UNI_DISPLAY_BACKSLASH to display the \\[nrfta\\] as the backslashed versions (like '\n') (UNI_DISPLAY_BACKSLASH is preferred over UNI_DISPLAY_ISPRINT for \\). UNI_DISPLAY_QQ (and its alias UNI_DISPLAY_REGEX) have both UNI_DISPLAY_BACKSLASH and UNI_DISPLAY_ISPRINT turned on.
The pointer to the PV of the dsv is returned.
char*pv_uni_display(SV *dsv, const U8 *spv, STRLEN len, STRLEN pvlim, UV flags)The encoding is assumed to be an Encode object, the PV of the ssv is assumed to be octets in that encoding and decoding the input starts from the position which (PV + *offset) pointed to. The dsv will be concatenated the decoded UTF-8 string from ssv. Decoding will terminate when the string tstr appears in decoding output or the input ends on the PV of the ssv. The value which the offset points will be modified to the last input position on the ssv.
Returns TRUE if the terminator was found, else returns FALSE.
boolsv_cat_decode(SV* dsv, SV *encoding, SV *ssv, int *offset, char* tstr, int tlen)The encoding is assumed to be an Encode object, on entry the PV of the sv is assumed to be octets in that encoding, and the sv will be converted into Unicode (and UTF-8).
If the sv already is UTF-8 (or if it is not POK), or if the encoding is not a reference, nothing is done to the sv. If the encoding is not anEncode::XS Encoding object, bad things will happen. (Seelib/encoding.pm andEncode).
The PV of the sv is returned.
char*sv_recode_to_utf8(SV* sv, SV *encoding)Build to the scalar dsv a displayable version of the scalar sv, the displayable version being at most pvlim bytes long (if longer, the rest is truncated and "..." will be appended).
The flags argument is as in pv_uni_display().
The pointer to the PV of the dsv is returned.
char*sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim, UV flags)The "p" contains the pointer to the UTF-8 string encoding the character that is being converted.
The "ustrp" is a pointer to the character buffer to put the conversion result to. The "lenp" is a pointer to the length of the result.
The "swashp" is a pointer to the swash to use.
Both the special and normal mappings are stored lib/unicore/To/Foo.pl, and loaded by SWASHNEW, using lib/utf8_heavy.pl. The special (usually, but not always, a multicharacter mapping), is tried first.
The "special" is a string like "utf8::ToSpecLower", which means the hash %utf8::ToSpecLower. The access to the hash is through Perl_to_utf8_case().
The "normal" is a string like "ToLower" which means the swash %utf8::ToLower.
UVto_utf8_case(const U8 *p, U8* ustrp, STRLEN *lenp, SV **swashp, const char *normal, const char *special)Convert the UTF-8 encoded character at p to its foldcase version and store that in UTF-8 in ustrp and its length in bytes in lenp. Note that the ustrp needs to be at least UTF8_MAXBYTES_CASE+1 bytes since the foldcase version may be longer than the original character (up to three characters).
The first character of the foldcased version is returned (but note, as explained above, that there may be more.)
UVto_utf8_fold(const U8 *p, U8* ustrp, STRLEN *lenp)Convert the UTF-8 encoded character at p to its lowercase version and store that in UTF-8 in ustrp and its length in bytes in lenp. Note that the ustrp needs to be at least UTF8_MAXBYTES_CASE+1 bytes since the lowercase version may be longer than the original character.
The first character of the lowercased version is returned (but note, as explained above, that there may be more.)
UVto_utf8_lower(const U8 *p, U8* ustrp, STRLEN *lenp)Convert the UTF-8 encoded character at p to its titlecase version and store that in UTF-8 in ustrp and its length in bytes in lenp. Note that the ustrp needs to be at least UTF8_MAXBYTES_CASE+1 bytes since the titlecase version may be longer than the original character.
The first character of the titlecased version is returned (but note, as explained above, that there may be more.)
UVto_utf8_title(const U8 *p, U8* ustrp, STRLEN *lenp)Convert the UTF-8 encoded character at p to its uppercase version and store that in UTF-8 in ustrp and its length in bytes in lenp. Note that the ustrp needs to be at least UTF8_MAXBYTES_CASE+1 bytes since the uppercase version may be longer than the original character.
The first character of the uppercased version is returned (but note, as explained above, that there may be more.)
UVto_utf8_upper(const U8 *p, U8* ustrp, STRLEN *lenp)flags
Returns the native character value 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.
Allows length and flags to be passed to low level routine.
UVutf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen, U32 flags)Bottom level UTF-8 decode routine. Returns the Unicode code point value of the first character in the strings which is assumed to be in UTF-8 encoding and no longer thancurlen;retlen will be set to the length, in bytes, of that character.
Ifs does not point to a well-formed UTF-8 character, the behaviour is dependent on the value offlags: if it contains UTF8_CHECK_ONLY, it is assumed that the caller will raise a warning, and this function will silently just setretlen to-1 and return zero. If theflags does not contain UTF8_CHECK_ONLY, warnings about malformations will be given,retlen will be set to the expected length of the UTF-8 character in bytes, and zero will be returned.
Theflags can also contain various flags to allow deviations from the strict UTF-8 encoding (seeutf8.h).
Most code should use utf8_to_uvchr() rather than call this directly.
UVutf8n_to_uvuni(const U8 *s, STRLEN curlen, STRLEN *retlen, U32 flags)Returns 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.
IVutf8_distance(const U8 *a, const U8 *b)Return the UTF-8 pointers displaced byoff characters, either forward or backward.
WARNING: do not use the following unless you *know*off is within the UTF-8 data pointed to bys *and* that on entrys is aligned on the first byte of character or just after the last byte of a character.
U8*utf8_hop(const U8 *s, I32 off)Return the length of the UTF-8 char encoded strings in characters. Stops ate (inclusive). Ife < s or if the scan would end up paste, croaks.
STRLENutf8_length(const U8* s, const U8 *e)Converts a strings of lengthlen from UTF-8 into native byte encoding. Unlikebytes_to_utf8, this over-writes the original string, and updates len to contain the new length. Returns zero on failure, settinglen to -1.
If you need a copy of the string, seebytes_from_utf8.
NOTE: this function is experimental and may change or be removed without notice.
U8*utf8_to_bytes(U8 *s, STRLEN *len)Returns the native character value 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.
Ifs does not point to a well-formed UTF-8 character, zero is returned and retlen is set, if possible, to -1.
UVutf8_to_uvchr(const U8 *s, STRLEN *retlen)Returns the Unicode 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.
This function should only be used when the returned UV is considered an index into the Unicode semantic tables (e.g. swashes).
Ifs does not point to a well-formed UTF-8 character, zero is returned and retlen is set, if possible, to -1.
UVutf8_to_uvuni(const U8 *s, STRLEN *retlen)Adds the UTF-8 representation of the Native codepointuv to the end of the stringd;d should be have at leastUTF8_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;U8*uvchr_to_utf8(U8 *d, UV uv)Adds the UTF-8 representation of the Unicode codepointuv to the end of the stringd;d should be have at leastUTF8_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 = uvuni_to_utf8_flags(d, uv, flags);or, in most cases,
d = uvuni_to_utf8(d, uv);(which is equivalent to)
d = uvuni_to_utf8_flags(d, uv, 0);is the recommended Unicode-aware way of saying
*(d++) = uv;U8*uvuni_to_utf8_flags(U8 *d, UV uv, UV flags)xsubpp andxsubpp internal functionsVariable 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.
I32axVariable which is setup byxsubpp to indicate the class name for a C++ XS constructor. This is always achar*. SeeTHIS.
char*CLASSSets up theax variable. This is usually handled automatically byxsubpp by callingdXSARGS.
dAX;Sets up theax variable and stack marker variablemark. This is usually handled automatically byxsubpp by callingdXSARGS.
dAXMARK;Sets up theitems variable. This is usually handled automatically byxsubpp by callingdXSARGS.
dITEMS;Sets up thepadoff_du variable for an XSUB that wishes to useUNDERBAR.
dUNDERBAR;Sets up stack and mark pointers for an XSUB, calling dSP and dMARK. Sets up theax anditems variables by callingdAX anddITEMS. This is usually handled automatically byxsubpp.
dXSARGS;Sets up theix variable for an XSUB which has aliases. This is usually handled automatically byxsubpp.
dXSI32;Variable which is setup byxsubpp to indicate the number of items on the stack. See"Variable-length Parameter Lists" in perlxs.
I32itemsVariable which is setup byxsubpp to indicate which of an XSUB's aliases was used to invoke it. See"The ALIAS: Keyword" in perlxs.
I32ixUsed byxsubpp to hook up XSUBs as Perl subs. Adds Perl prototypes to the subs.
Variable 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.
(whatever)RETVALUsed to access elements on the XSUB's stack.
SV*ST(int ix)Variable which is setup byxsubpp to designate the object in a C++ XSUB. This is always the proper type for the C++ object. SeeCLASS and"Using XS With C++" in perlxs.
(whatever)THISThe SV* corresponding to the $_ variable. Works even if there is a lexical $_ in scope.
Macro to declare an XSUB and its C parameter list. This is handled byxsubpp.
The version identifier for an XS module. This is usually handled automatically byExtUtils::MakeMaker. SeeXS_VERSION_BOOTCHECK.
Macro to verify that a PM module's $VERSION variable matches the XS module'sXS_VERSION variable. This is usually handled automatically byxsubpp. See"The VERSIONCHECK: Keyword" in perlxs.
XS_VERSION_BOOTCHECK;This is the XSUB-writer's interface to Perl'sdie function. Normally call this function the same way you call the Cprintf function. Callingcroak returns control directly to Perl, sidestepping the normal C order of execution. Seewarn.
If you want to throw an exception object, assign the object to$@ and then passNULL to croak():
errsv = get_sv("@", GV_ADD); sv_setsv(errsv, exception_object); croak(NULL);voidcroak(const char* pat, ...)This is the XSUB-writer's interface to Perl'swarn function. Call this function the same way you call the Cprintf function. Seecroak.
voidwarn(const char* pat, ...)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.
perlguts(1), perlxs(1), perlxstut(1), perlintern(1)
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