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mbrlen(3p) — Linux manual page

MBRLEN(3P)              POSIX Programmer's ManualMBRLEN(3P)

PROLOG        top

       This manual page is part of the POSIX Programmer's Manual.  The       Linux implementation of this interface may differ (consult the       corresponding Linux manual page for details of Linux behavior), or       the interface may not be implemented on Linux.

NAME        top

       mbrlen — get number of bytes in a character (restartable)

SYNOPSIS        top

       #include <wchar.h>       size_t mbrlen(const char *restricts, size_tn,           mbstate_t *restrictps);

DESCRIPTION        top

       The functionality described on this reference page is aligned with       the ISO C standard. Any conflict between the requirements       described here and the ISO C standard is unintentional. This       volume of POSIX.1‐2017 defers to the ISO C standard.       Ifs is not a null pointer,mbrlen() shall determine the number of       bytes constituting the character pointed to bys.  It shall be       equivalent to:           mbstate_t internal;           mbrtowc(NULL, s, n, ps != NULL ? ps : &internal);       Ifps is a null pointer, thembrlen() function shall use its own       internalmbstate_tobject, which is initialized at program start-       up to the initial conversion state. Otherwise, thembstate_t       object pointed to byps shall be used to completely describe the       current conversion state of the associated character sequence. The       implementation shall behave as if no function defined in this       volume of POSIX.1‐2017 callsmbrlen().       The behavior of this function is affected by theLC_CTYPE category       of the current locale.       Thembrlen() function need not be thread-safe if called with a       NULLps argument.       Thembrlen() function shall not change the setting oferrno if       successful.

RETURN VALUE        top

       Thembrlen() function shall return the first of the following that       applies:       0           If the nextn or fewer bytes complete the character                   that corresponds to the null wide character.positive    If the nextn or fewer bytes complete a valid                   character; the value returned shall be the number of                   bytes that complete the character.       (size_t)-2  If the nextn bytes contribute to an incomplete but                   potentially valid character, and alln bytes have been                   processed. Whenn has at least the value of the                   {MB_CUR_MAX} macro, this case can only occur ifs                   points at a sequence of redundant shift sequences (for                   implementations with state-dependent encodings).       (size_t)-1  If an encoding error occurs, in which case the nextn                   or fewer bytes do not contribute to a complete and                   valid character. In this case,[EILSEQ]shall be                   stored inerrno and the conversion state is undefined.

ERRORS        top

       Thembrlen() function shall fail if:EILSEQAn invalid character sequence is detected.  In the POSIX              locale an[EILSEQ]error cannot occur since all byte values              are valid characters.       Thembrlen() function may fail if:EINVALps points to an object that contains an invalid conversion              state.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

mbsinit(3p),mbrtowc(3p)       The Base Definitions volume of POSIX.1‐2017,wchar.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 by the Institute of Electrical and Electronics Engineers,       Inc and The Open Group.  In the event of any discrepancy between       this version and the original IEEE and The Open Group Standard,       the original IEEE and The Open Group Standard is the referee       document. The original Standard can be obtained online athttp://www.opengroup.org/unix/online.html .       Any typographical or formatting errors that appear in this page       are most likely to have been introduced during the conversion of       the source files to man page format. To report such errors, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017MBRLEN(3P)

Pages that refer to this page:wchar.h(0p), mbsinit(3p)

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