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.

GNU                                               July 25, 1999                                         MBLEN(3)