Section: Linux Programmer's Manual (3)
wcstombs - convert a wide-character string to a multibyte string
size_t wcstombs(char *dest, const wchar_t *src, size_t n);
is not NULL, the
the wide-character string
to a multibyte string starting at
bytes are written to
The sequence of characters placed in
begins in the initial shift state.
The conversion can stop for three reasons:
A wide character has been encountered that can not be represented as a
multibyte sequence (according to the current locale).
In this case,
The length limit forces a stop.
In this case, the number of bytes written to
is returned, but the shift state at this point is lost.
The wide-character string has been completely converted, including the
terminating null wide character (L'\0').
In this case, the conversion ends in the initial shift state.
The number of bytes written to
excluding the terminating null byte ('\0'), is returned.
The programmer must ensure that there is room for at least
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
is greater than or equal to
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
For an explanation of the terms used in this section, see
POSIX.1-2001, POSIX.1-2008, C99.
The behavior of
depends on the
category of the
provides a better interface to the same functionality.
This page is part of release 5.10 of the Linux
A description of the project,
information about reporting bugs,
and the latest version of this page,
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