wcstombs(3p) — Linux manual page
WCSTOMBS(3P) POSIX Programmer's Manual WCSTOMBS(3P)
PROLOG
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
wcstombs — convert a wide-character string to a character string
SYNOPSIS
#include <stdlib.h>
size_t wcstombs(char *restrict s, const wchar_t *restrict pwcs,
size_t n);
DESCRIPTION
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 wcstombs() function shall convert the sequence of wide-
character codes that are in the array pointed to by pwcs into a
sequence of characters that begins in the initial shift state and
store these characters into the array pointed to by s, stopping
if a character would exceed the limit of n total bytes or if a
null byte is stored. Each wide-character code shall be converted
as if by a call to wctomb(), except that the shift state of
wctomb() shall not be affected.
The behavior of this function shall be affected by the LC_CTYPE
category of the current locale.
No more than n bytes shall be modified in the array pointed to by
s. If copying takes place between objects that overlap, the
behavior is undefined. If s is a null pointer, wcstombs() shall
return the length required to convert the entire array regardless
of the value of n, but no values are stored.
RETURN VALUE
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 is n.
ERRORS
The wcstombs() function shall fail if:
EILSEQ A wide-character code does not correspond to a valid
character.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
mblen(3p), mbtowc(3p), mbstowcs(3p), wctomb(3p)
The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)
COPYRIGHT
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 WCSTOMBS(3P)
Pages that refer to this page: ctype.h(0p), stdlib.h(0p), mblen(3p), mbstowcs(3p), mbtowc(3p), setlocale(3p), wctomb(3p)