wctomb(3p) — Linux manual page


WCTOMB(3P)                POSIX Programmer's Manual               WCTOMB(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

       wctomb — convert a wide-character code to a character

SYNOPSIS         top

       #include <stdlib.h>

       int wctomb(char *s, wchar_t wchar);

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.1‐2008 defers to the ISO C standard.

       The wctomb() function shall determine the number of bytes needed to
       represent the character corresponding to the wide-character code
       whose value is wchar (including any change in the shift state). It
       shall store the character representation (possibly multiple bytes and
       any special bytes to change shift state) in the array object pointed
       to by s (if s is not a null pointer). At most {MB_CUR_MAX} bytes
       shall be stored. If wchar is 0, a null byte shall be stored, preceded
       by any shift sequence needed to restore the initial shift state, and
       wctomb() shall be left in the initial shift state.

       The behavior of this function is affected by the LC_CTYPE category of
       the current locale. For a state-dependent encoding, this function
       shall be placed into its initial state by a call for which its
       character pointer argument, s, is a null pointer. Subsequent calls
       with s as other than a null pointer shall cause the internal state of
       the function to be altered as necessary. A call with s as a null
       pointer shall cause this function to return a non-zero value if
       encodings have state dependency, and 0 otherwise. Changing the
       LC_CTYPE category causes the shift state of this function to be

       The wctomb() function need not be thread-safe.

       The implementation shall behave as if no function defined in this
       volume of POSIX.1‐2008 calls wctomb().

RETURN VALUE         top

       If s is a null pointer, wctomb() shall return a non-zero or 0 value,
       if character encodings, respectively, do or do not have state-
       dependent encodings. If s is not a null pointer, wctomb() shall
       return −1 if the value of wchar does not correspond to a valid
       character, or return the number of bytes that constitute the
       character corresponding to the value of wchar.

       In no case shall the value returned be greater than the value of the
       {MB_CUR_MAX} macro.

ERRORS         top

       The wctomb() function shall fail if:

       EILSEQ An invalid wide-character code is detected.

       The following sections are informative.

EXAMPLES         top




RATIONALE         top




SEE ALSO         top

       mblen(3p), mbtowc(3p), mbstowcs(3p), wcstombs(3p)

       The Base Definitions volume of POSIX.1‐2008, stdlib.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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 at http://www.unix.org/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, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                          WCTOMB(3P)

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