mblen - determine number of bytes in next multibyte character


   #include <stdlib.h>

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


   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 multibyte
   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


   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.


   For   an   explanation   of   the  terms  used  in  this  section,  see

   Interface  Attribute      Value          
   mblen()    Thread safety  MT-Unsafe race 


   POSIX.1-2001, POSIX.1-2008, C99.


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

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




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   description  of  the project, information about reporting bugs, and the
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