NAME

wcrtomb, c16rtomb, c32rtomb —

convert a wide-character code to a character (restartable)

LIBRARY

Standard C Library (libc, -lc)

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);

DESCRIPTION

The wcrtomb(), c16rtomb() and c32rtomb() 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.

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(), c16rtomb() and c32rtomb() functions will fail if:

[EILSEQ]: An invalid wide character code was specified.
[EINVAL]: The conversion state is invalid.

STANDARDS

The wcrtomb(), c16rtomb() and c32rtomb() functions conform to ISO/IEC 9899:2011 (“ISO C11”).