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MBRLEN(3P)                 POSIX Programmer's Manual                MBRLEN(3P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
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 equiva-
       lent 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 inter-
       nal  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  corre-
              sponds 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(3P)