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wcstombs(3p) — Linux manual page

WCSTOMBS(3P)            POSIX Programmer's ManualWCSTOMBS(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

       wcstombs — convert a wide-character string to a character string

SYNOPSIS        top

       #include <stdlib.h>       size_t wcstombs(char *restricts, const wchar_t *restrictpwcs,           size_tn);

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.       Thewcstombs() function shall convert the sequence of wide-       character codes that are in the array pointed to bypwcs into a       sequence of characters that begins in the initial shift state and       store these characters into the array pointed to bys, stopping if       a character would exceed the limit ofn total bytes or if a null       byte is stored. Each wide-character code shall be converted as if       by a call towctomb(), except that the shift state ofwctomb()       shall not be affected.       The behavior of this function shall be affected by theLC_CTYPE       category of the current locale.       No more thann bytes shall be modified in the array pointed to bys.  If copying takes place between objects that overlap, the       behavior is undefined.  Ifs is a null pointer,wcstombs() shall       return the length required to convert the entire array regardless       of the value ofn, but no values are stored.

RETURN VALUE        top

       If a wide-character code is encountered that does not correspond       to a valid character (of one or more bytes each),wcstombs() shall       return (size_t)-1. Otherwise,wcstombs() shall return the number       of bytes stored in the character array, not including any       terminating null byte. The array shall not be null-terminated if       the value returned isn.

ERRORS        top

       Thewcstombs() function shall fail if:EILSEQA wide-character code does not correspond to a valid              character.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

mblen(3p),mbtowc(3p),mbstowcs(3p),wctomb(3p)       The Base Definitions volume of POSIX.1‐2017,stdlib.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                2017WCSTOMBS(3P)

Pages that refer to this page:ctype.h(0p), stdlib.h(0p), mblen(3p), mbstowcs(3p), mbtowc(3p), setlocale(3p), wctomb(3p)

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