wcrtomb(3p) — Linux manual page


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

       wcrtomb — convert a wide-character code to a character (restartable)

SYNOPSIS         top

       #include <wchar.h>

       size_t wcrtomb(char *restrict s, wchar_t wc, mbstate_t *restrict ps);

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.

       If s is a null pointer, the wcrtomb() function shall be equivalent to
       the call:

           wcrtomb(buf, L'\0', ps)

       where buf is an internal buffer.

       If s is not a null pointer, the wcrtomb() function shall determine
       the number of bytes needed to represent the character that
       corresponds to the wide character given by wc (including any shift
       sequences), and store the resulting bytes in the array whose first
       element is pointed to by s.  At most {MB_CUR_MAX} bytes are stored.
       If wc is a null wide character, a null byte shall be stored, preceded
       by any shift sequence needed to restore the initial shift state. The
       resulting state described shall be the initial conversion state.

       If ps is a null pointer, the wcrtomb() function shall use its own
       internal mbstate_t object, which is initialized at program start-up
       to the initial conversion state. Otherwise, the mbstate_t object
       pointed to by ps 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.1‐2008 calls wcrtomb().

       The wcrtomb() function need not be thread-safe if called with a NULL
       ps argument.

       The behavior of this function shall be affected by the LC_CTYPE
       category of the current locale.

       The wcrtomb() function shall not change the setting of errno if

RETURN VALUE         top

       The wcrtomb() function shall return the number of bytes stored in the
       array object (including any shift sequences). When wc is not a valid
       wide character, an encoding error shall occur. In this case, the
       function shall store the value of the macro [EILSEQ] in errno and
       shall return (size_t)−1; the conversion state shall be undefined.

ERRORS         top

       The wcrtomb() function shall fail if:

       EILSEQ An invalid wide-character code is detected.

       The wcrtomb() function may fail if:

       EINVAL ps points to an object that contains an invalid conversion

       The following sections are informative.

EXAMPLES         top




RATIONALE         top




SEE ALSO         top

       mbsinit(3p), wcsrtombs(3p)

       The Base Definitions volume of POSIX.1‐2008, wchar.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                         WCRTOMB(3P)

Pages that refer to this page: wchar.h(0p)fprintf(3p)fscanf(3p)fwscanf(3p)mbsinit(3p)wcsrtombs(3p)