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 a NULL pointer, the mblen function inspects at most n bytes of the multibyte
       string starting at s and extracts the next complete multibyte character. It uses a  static
       anonymous  shift state only known 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 >= 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 a NULL pointer, the mblen function resets the shift  state,  only  known  to  this
       function, to the initial state, and returns non-zero if the encoding has non-trivial 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 recognized.  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.

CONFORMING TO

       ISO/ANSI C, UNIX98

SEE ALSO

       mbrlen(3)

NOTES

       The behaviour of mblen depends on the LC_CTYPE category of the current locale.

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