MBRTOWC(3) BSD Library Functions Manual MBRTOWC(3)
NAME
mbrtowc, mbrtoc16, mbrtoc32 -- convert a character to a wide-character code (restartable)
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <wchar.h>
size_t
mbrtowc(wchar_t * restrict pc, const char * restrict s, size_t n, mbstate_t * restrict ps);
#include <uchar.h>
size_t
mbrtoc16(char16_t * restrict pc, const char * restrict s, size_t n, mbstate_t * restrict ps);
size_t
mbrtoc32(char32_t * restrict pc, const char * restrict s, size_t n, mbstate_t * restrict ps);
DESCRIPTION
The mbrtowc(), mbrtoc16() and mbrtoc32() functions inspect at most n bytes pointed to by s to determine the number of bytes needed to com-
plete the next multibyte character. If a character can be completed, and pc is not NULL, the wide character which is represented by s is
stored in the wchar_t, char16_t or char32_t it points to.
If s is NULL, these functions behave as if pc was NULL, s was an empty string ("") and n was 1.
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 a single char16_t is not large enough to represent certain multibyte characters, the mbrtoc16() function may need to be invoked multiple
times to convert a single multibyte character sequence.
RETURN VALUES
The mbrtowc(), mbrtoc16() and mbrtoc32() functions return:
0 The next n or fewer bytes represent the null wide character (L' ').
>0 The next n or fewer bytes represent a valid character, these functions return the number of bytes used to complete the multibyte
character.
(size_t)-1
An encoding error has occurred. The next n or fewer bytes do not contribute to a valid multibyte character.
(size_t)-2
The next n contribute to, but do not complete, a valid multibyte character sequence, and all n bytes have been processed.
The mbrtoc16() function also returns:
(size_t)-3
The next character resulting from a previous call has been stored. No bytes from the input have been consumed.
ERRORS
The mbrtowc(), mbrtoc16() and mbrtoc32() functions will fail if:
[EILSEQ] An invalid multibyte sequence was detected.
[EINVAL] The conversion state is invalid.
SEE ALSO
mbtowc(3), multibyte(3), setlocale(3), wcrtomb(3)
STANDARDS
The mbrtowc(), mbrtoc16() and mbrtoc32() functions conform to ISO/IEC 9899:2011 (``ISO C11'').
BSD
May 21, 2013 BSD