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MBRTOWC(3) FreeBSD 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 complete
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').
>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
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").
FreeBSD 14.0-RELEASE-p11 May 21, 2013 FreeBSD 14.0-RELEASE-p11