MBRTOWC(3) BSD Library Functions Manual MBRTOWC(3)NAME
mbrtowc, mbrtowc_l — 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 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);
DESCRIPTION
The mbrtowc() function inspects at most n bytes, pointed to by s, to
determine the number of bytes needed to complete the next multibyte char‐
acter. 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 infor‐
mation.
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 char‐
acter.
(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.
SEE ALSOmbtowc(3), multibyte(3), setlocale(3), wcrtomb(3), xlocale(3)STANDARDS
The mbrtowc() function conforms to ISO/IEC 9899:1999 (“ISO C99”).
BSD April 8, 2004 BSD
