NAME

       mbrlen - get number of bytes in a character (restartable)

SYNOPSIS

       #include <wchar.h>

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

DESCRIPTION

       If  s  is  not  a  null  pointer, mbrlen() shall determine the number of bytes constituting the character
       pointed to by s. It shall be equivalent to:

              mbstate_t internal;
              mbrtowc(NULL, s, n, ps != NULL ? ps : &internal);

       If ps is a null pointer, the mbrlen() function shall use its own  internal  mbstate_t  object,  which  is
       initialized  at program start-up to the initial conversion state. Otherwise, the mbstate_t object pointed
       to by ps shall be used to completely describe the current conversion state of  the  associated  character
       sequence.   The   implementation   shall   behave   as   if   no  function  defined  in  this  volume  of
       IEEE Std 1003.1-2001 calls mbrlen().

       The behavior of this function is affected by the LC_CTYPE category of the current locale.

RETURN VALUE

       The mbrlen() function shall return the first of the following that applies:

       0      If the next n or fewer bytes complete the character that corresponds to the null wide character.

       positive
              If the next n or fewer bytes complete a valid character; the value returned shall be the number of
              bytes that complete the character.

       (size_t)-2
              If the next n bytes contribute to an incomplete but potentially valid character, and all  n  bytes
              have  been  processed. When n has at least the value of the {MB_CUR_MAX} macro, this case can only
              occur if s points at a sequence of redundant shift  sequences  (for  implementations  with  state-
              dependent encodings).

       (size_t)-1
              If  an  encoding  error  occurs,  in  which  case the next n or fewer bytes do not contribute to a
              complete and valid character. In this case, [EILSEQ] shall be stored in errno and  the  conversion
              state is undefined.

ERRORS

       The mbrlen() function may fail if:

       EINVAL ps points to an object that contains an invalid conversion state.

       EILSEQ Invalid character sequence is detected.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       mbsinit() , mbrtowc() , the Base Definitions volume of IEEE Std 1003.1-2001, <wchar.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers,
       Inc and The Open Group. In the event of any discrepancy between this version and the  original  IEEE  and
       The  Open  Group  Standard,  the  original  IEEE and The Open Group Standard is the referee document. The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                                   2003                                             MBRLEN(P)