WCSTOMBS(3) Linux Programmer's Manual WCSTOMBS(3)NAMEwcstombs - convert a wide-character string to a multibyte string
SYNOPSIS
#include <stdlib.h>
size_t wcstombs(char *dest, const wchar_t *src, size_t n);
DESCRIPTION
If dest is not NULL, the wcstombs() function converts the wide-charac‐
ter string src to a multibyte string starting at dest. At most n bytes
are written to dest. The sequence of characters placed in dest begins
in the initial shift state. The conversion can stop for three reasons:
1. A wide character has been encountered that can not be represented as
a multibyte sequence (according to the current locale). In this
case, (size_t) -1 is returned.
2. The length limit forces a stop. In this case, the number of bytes
written to dest is returned, but the shift state at this point is
lost.
3. The wide-character string has been completely converted, including
the terminating null wide character (L'\0'). In this case, the con‐
version ends in the initial shift state. The number of bytes writ‐
ten to dest, excluding the terminating null byte ('\0'), is
returned.
The programmer must ensure that there is room for at least n bytes at
dest.
If dest is NULL, n is ignored, and the conversion proceeds as above,
except that the converted bytes are not written out to memory, and no
length limit exists.
In order to avoid the case 2 above, the programmer should make sure n
is greater than or equal to wcstombs(NULL,src,0)+1.
RETURN VALUE
The wcstombs() function returns the number of bytes that make up the
converted part of a multibyte sequence, not including the terminating
null byte. If a wide character was encountered which could not be con‐
verted, (size_t) -1 is returned.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
┌───────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├───────────┼───────────────┼─────────┤
│wcstombs() │ Thread safety │ MT-Safe │
└───────────┴───────────────┴─────────┘
CONFORMING TO
POSIX.1-2001, POSIX.1-2008, C99.
NOTES
The behavior of wcstombs() depends on the LC_CTYPE category of the cur‐
rent locale.
The function wcsrtombs(3) provides a better interface to the same func‐
tionality.
SEE ALSOmblen(3), mbstowcs(3), mbtowc(3), wcsrtombs(3)wctomb(3)COLOPHON
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latest version of this page, can be found at
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GNU 2017-09-15 WCSTOMBS(3)
