WCRTOMB(3)

NAME
wcrtomb, wcrtomb_l, c16rtomb, c16rtomb_l, c32rtomb, c32rtomb_l - convert a wide-character code to a character (restartable)

LIBRARY
libc

SYNOPSIS
#include <wchar.h>
size_t
wcrtomb(char * restrict s, wchar_t c, mbstate_t * restrict ps);
#include <uchar.h>
size_t
c16rtomb(char * restrict s, char16_t c, mbstate_t * restrict ps);
size_t
c32rtomb(char * restrict s, char32_t c, mbstate_t * restrict ps);
#include <xlocale.h>
size_t
wcrtomb_l(char * restrict s, wchar_t c, mbstate_t * restrict ps, locale_t locale);
size_t
c16rtomb_l(char * restrict s, char16_t c, mbstate_t * restrict ps, locale_t locale);
size_t
c32rtomb_l(char * restrict s, char32_t c, mbstate_t * restrict ps, locale_t);

DESCRIPTION
The wcrtomb(), wcrtomb_l(), c16rtomb(), c16rtomb_l(), c32rtomb(), and c32rtomb_l() functions store a multibyte sequence representing the wide character c, including any necessary shift sequences, to the character array s, storing a maximum of MB_CUR_MAX bytes.

If s is NULL, these functions behave as if s pointed to an internal buffer and c was a null wide character (L'\0').

The mbstate_t argument, ps, is used to keep track of the shift state. If it is NULL, these functions use an internal, static mbstate_t object, which is initialized to the initial conversion state at program startup.

As certain multibyte characters may only be represented by a series of 16-bit characters, the c16rtomb() may need to invoked multiple times before a multibyte sequence is returned.

The wcrtomb_l(), c16rtomb_l(), and c32rtomb_l() functions take an explicit locale argument, whereas the wcrtomb(), c16rtomb(), and c32rtomb() functions use the current global or per-thread locale.

RETURN VALUES
These functions return the length (in bytes) of the multibyte sequence needed to represent c, or (size_t)-1 if c is not a valid wide character code.

ERRORS
The wcrtomb(), wcrtomb_l(), c16rtomb(), c16rtomb_l(), c32rtomb(), and c32rtomb_l() functions will fail if:

[EILSEQ]
    An invalid wide character code was specified.

[EINVAL]
    The conversion state is invalid.

SEE ALSO
mbrtowc(3), multibyte(3), setlocale(3), wcrtombin(3), wcrtoutf8(3), wctomb(3), xlocale(3)

STANDARDS
The wcrtomb(), c16rtomb() and c32rtomb() functions conform to isoC-2011.