WCTOMB(3) Linux Programmer's Manual WCTOMB(3)NAMEwctomb - convert a wide character to a multibyte sequence
int wctomb(char *s, wchar_t wc);
If s is not NULL, the wctomb() function converts the wide character wc
to its multibyte representation and stores it at the beginning of the
character array pointed to by s. It updates the shift state, which is
stored in a static anonymous variable known only to the wctomb() func‐
tion, and returns the length of said multibyte representation, that is,
the number of bytes written at s.
The programmer must ensure that there is room for at least MB_CUR_MAX
bytes at s.
If s is NULL, the wctomb() function resets the shift state, known only
to this function, to the initial state, and returns nonzero if the
encoding has nontrivial shift state, or zero if the encoding is state‐
If s is not NULL, the wctomb() function returns the number of bytes
that have been written to the byte array at s. If wc can not be repre‐
sented as a multibyte sequence (according to the current locale), -1 is
If s is NULL, the wctomb() function returns nonzero if the encoding has
nontrivial shift state, or zero if the encoding is stateless.
Multithreading (see pthreads(7))
The wctomb() function is not thread-safe.
The behavior of wctomb() depends on the LC_CTYPE category of the cur‐
The function wcrtomb(3) provides a better interface to the same func‐
SEE ALSOMB_CUR_MAX(3), mblen(3), mbstowcs(3), mbtowc(3), wcrtomb(3),
This page is part of release 3.65 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 2014-03-18 WCTOMB(3)