x11r4 man page for mblen

MBLEN(3)						     Linux Programmer's Manual							  MBLEN(3)

NAME
       mblen - determine number of bytes in next multibyte character

SYNOPSIS
       #include <stdlib.h>

       int mblen(const char *s, size_t n);

DESCRIPTION
       If s is not NULL, the mblen() function inspects at most n bytes of the multibyte string starting at s and extracts the next complete multi-
       byte character.	It uses a static anonymous shift state known only to the mblen() function.  If the multibyte character	is  not  the  null
       wide  character,  it  returns  the  number  of  bytes that were consumed from s.  If the multibyte character is the null wide character, it
       returns 0.

       If the n bytes starting at s do not contain a complete multibyte character, mblen() returns -1.	This can happen even if n is greater  than
       or equal to MB_CUR_MAX, if the multibyte string contains redundant shift sequences.

       If the multibyte string starting at s contains an invalid multibyte sequence before the next complete character, mblen() also returns -1.

       If  s  is  NULL, the mblen() function resets the shift state, known to only this function, to the initial state, and returns nonzero if the
       encoding has nontrivial shift state, or zero if the encoding is stateless.

RETURN VALUE
       The mblen() function returns the number of bytes parsed from the multibyte sequence starting at s, if a non-null wide character was  recog-
       nized.	It  returns  0, if a null wide character was recognized.  It returns -1, if an invalid multibyte sequence was encountered or if it
       couldn't parse a complete multibyte character.

ATTRIBUTES
       For an explanation of the terms used in this section, see attributes(7).

       +----------+---------------+----------------+
       |Interface | Attribute	  | Value	   |
       +----------+---------------+----------------+
       |mblen()   | Thread safety | MT-Unsafe race |
       +----------+---------------+----------------+
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, C99.

NOTES
       The behavior of mblen() depends on the LC_CTYPE category of the current locale.

       The function mbrlen(3) provides a better interface to the same functionality.

SEE ALSO
       mbrlen(3)

COLOPHON
       This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

GNU
								    2015-08-08								  MBLEN(3)