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WCRTOMB(3) FreeBSD Library Functions Manual WCRTOMB(3)
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.
SEE ALSO
mbrtowc(3), multibyte(3), setlocale(3), wctomb(3)
STANDARDS
The wcrtomb(), c16rtomb() and c32rtomb() functions conform to ISO/IEC
9899:2011 ("ISO C11").