|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT |
|
|
|
WCTOMB(3P) POSIX Programmer's Manual WCTOMB(3P)
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.
wctomb — convert a wide-character code to a character
#include <stdlib.h>
int wctomb(char *s, wchar_t wchar);
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.
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 unspecified.
The wctomb() function need not be thread-safe.
The implementation shall behave as if no function defined in this
volume of POSIX.1‐2017 calls wctomb().
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.
The wctomb() function shall fail if:
EILSEQ An invalid wide-character code is detected.
The following sections are informative.
None.
None.
None.
None.
mblen(3p), mbtowc(3p), mbstowcs(3p), wcstombs(3p)
The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)
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 at
http://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, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2017 WCTOMB(3P)
Pages that refer to this page: ctype.h(0p), stdlib.h(0p), mblen(3p), mbstowcs(3p), mbtowc(3p), setlocale(3p), wcstombs(3p)
|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|