wcrtomb (3) - Linux Man Pages
wcrtomb: convert a wide character to a multibyte sequence
wcrtomb - convert a wide character to a multibyte sequence
#include <wchar.h> size_t wcrtomb(char *s, wchar_t wc, mbstate_t *ps);
DESCRIPTIONThe main case for this function is when s is not NULL and wc is not a null wide character (L'\0'). In this case, the wcrtomb() 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 *ps, and returns the length of said multibyte representation, that is, the number of bytes written at s.
A different case is when s is not NULL, but wc is a null wide character (L'\0'). In this case, the wcrtomb() function stores at the character array pointed to by s the shift sequence needed to bring *ps back to the initial state, followed by a '\0' byte. It updates the shift state *ps (i.e., brings it into the initial state), and returns the length of the shift sequence plus one, that is, the number of bytes written at s.
A third case is when s is NULL. In this case, wc is ignored, and the function effectively returns
is an internal anonymous buffer.
function returns the number of
bytes that have been or would
have been written to the byte array at
can not be
represented as a multibyte sequence (according to the current locale),
is returned, and
For an explanation of the terms used in this section, see
Interface Attribute Value
Thread safety MT-Unsafe race:wcrtomb/!ps
POSIX.1-2001, POSIX.1-2008, C99.
The behavior of
depends on the
category of the
This page is part of release 5.05 of the Linux
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where buf is an internal anonymous buffer.