mbrtowc3
Convert a character to a wide-character code (restartable)
Usage
#include <wchar.h>
size_t
mbrtowc(wchar_t *restrict pwc, const char *restrict s, size_t n, mbstate_t *restrict ps);
#include <wchar.h>
#include <xlocale.h>
size_t
mbrtowc_l(wchar_t *restrict pwc, const char *restrict s, size_t n, mbstate_t *restrict ps, locale_t loc);
Library
Standard C Library (libc, -lc)
Overview
The mbrtowc() function inspects 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 pwc is not NULL, the wide character which is represented by s is stored in the wchar_t it points to.
If s is NULL, mbrtowc() behaves as if pwc were NULL, s were an empty string (""), and n were 1.
The mbstate_t argument, ps, is used to keep track of the shift state. If it is NULL, mbrtowc() uses an internal, static mbstate_t object, which is initialized to the initial conversion state at program startup.
While the mbrtowc() function uses the current locale, the mbrtowc_l() function may be passed a locale directly. See xlocale(3) for more information.
Return values
The mbrtowc() functions returns:
- 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,
mbrtowc() returns the number of bytes used to complete the 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.
- (size_t)-1
-
An encoding error has occurred. The next n or fewer bytes do not contribute to a valid multibyte character.
Errors
The mbrtowc() function will fail if:
- [EILSEQ]
-
An invalid multibyte sequence was detected.
- [EINVAL]
-
The conversion state is invalid.
Releases
145 releases since Mac OS X 10.3; the text changed 2 times.