illumos: manual page: mbtowc.3c

MBTOWC(3C) Standard C Library Functions MBTOWC(3C)

NAME

mbtowc, mbtowc_l - convert a character to a wide-character code

SYNOPSIS

#include <stdlib.h>

int mbtowc(wchar_t *restrict pwc, const char *restrict s, size_t n);

#include <stdlib.h>
#include <xlocale.h>

int mbtowc_l(wchar_t *restrict pwc, const char *restrict s, size_t n,
locale_t loc);

DESCRIPTION

If s is not a null pointer, mbtowc() determines the number of the bytes
that constitute the character pointed to by s. It then determines the
wide-character code for the value of type wchar_t that corresponds to
that character. (The value of the wide-character code corresponding to
the null byte is 0.) If the character is valid and pwc is not a null
pointer, mbtowc() stores the wide-character code in the object pointed to
by pwc.

A call with s as a null pointer causes this function to return 0. The
behavior of this function is affected by the LC_CTYPE category of the
current locale. At most n bytes of the array pointed to by s will be
examined.

The function mbtowc_l() behaves identically to mbtowc(), except instead
of using the current locale, it uses the locale as specified by loc.

RETURN VALUES

If s is a null pointer, these functions return 0. If s is not a null
pointer, they return 0 (if s points to the null byte), the number of
bytes that constitute the converted character (if the next n or fewer
bytes form a valid character), or -1 and may set errno to indicate the
error (if they do not form a valid character).

In no case will the value returned be greater than n or the value of the
MB_CUR_MAX macro.

ERRORS

The mbtowc() and mbtowc_l() functions may fail if:

EILSEQ
Invalid character sequence is detected.