#include <wchar.h>

       size_t mbrlen(const char *s, size_t n, mbstate_t *ps);

       The  mbrlen() function inspects at most n bytes of the multibyte string
       starting at s and extracts the next complete multibyte  character.   It
       updates  the  shift  state  *ps.  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
       resets the shift state *ps to the initial state and returns 0.

       If the n bytes starting at s do not contain a complete multibyte  char-
       acter,  mbrlen()  returns  (size_t) -2.   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,  mbrlen()  returns
       (size_t) -1 and sets errno to EILSEQ.  In this case, the effects on *ps
       are undefined.

       If  ps  is  a  NULL pointer, a static anonymous state known only to the
       mbrlen() function is used instead.

       The mbrlen() function returns the  number  of  bytes  parsed  from  the
       multibyte sequence starting at s, if a non-null wide character was rec-
       ognized.  It returns 0, if a null wide character  was  recognized.   It
       returns  (size_t) -1  and sets errno to EILSEQ, if an invalid multibyte
       sequence was encountered.  It returns (size_t) -2 if it couldn't  parse
       a complete multibyte character, meaning that n should be increased.

   Multithreading (see pthreads(7))
       The  mbrlen()  function  is  thread-safe  with  exceptions.   It is not
       thread-safe if called with a NULL ps parameter.


       The behavior of mbrlen() depends on the LC_CTYPE category of  the  cur-
       rent locale.


       This  page  is  part of release 3.54 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.
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