Copyright (c) 1993
The Regents of the University of California. All rights reserved.
This code is derived from software contributed to Berkeley by
Donn Seeley of BSDI.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
4. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
From @(#)multibyte.3 8.1 (Berkeley) 6/4/93
From FreeBSD: src/lib/libc/locale/multibyte.3,v 1.22 2003/11/08 03:23:11 tjr Exp
$FreeBSD$
.Dd April 11, 2004 .Dt MBTOWC 3 .Os .Sh NAME .Nm mbtowc .Nd convert a character to a wide-character code .Sh LIBRARY .Lb libc .Sh SYNOPSIS n stdlib.h .Ft int .Fo mbtowc .Fa "wchar_t * restrict wcharp" "const char * restrict mbchar" .Fa "size_t nbytes" .Fc .Sh DESCRIPTION The .Fn mbtowc function converts a multibyte character .Fa mbchar into a wide character according to the current conversion state, and stores the result in the object pointed to by .Fa wcharp . Up to .Fa nbytes bytes are examined.
p A call with a null .Fa mbchar pointer returns nonzero if the current encoding requires shift states, zero otherwise; if shift states are required, the shift state is reset to the initial state. .Sh RETURN VALUES If .Fa mbchar is .Dv NULL , the .Fn mbtowc function returns nonzero if shift states are supported, zero otherwise.
p Otherwise, if .Fa mbchar is not a null pointer, .Fn mbtowc either returns 0 if .Fa mbchar represents the null wide character, or returns the number of bytes processed in .Fa mbchar , or returns -1 if no multibyte character could be recognized or converted. In this case, .Fn mbtowc Ns 's internal conversion state is undefined. .Sh ERRORS The .Fn mbtowc function will fail if: l -tag -width Er t Bq Er EILSEQ An invalid multibyte sequence was detected. t Bq Er EINVAL The internal conversion state is invalid. .El .Sh SEE ALSO .Xr btowc 3 , .Xr mblen 3 , .Xr mbrtowc 3 , .Xr mbstowcs 3 , .Xr multibyte 3 , .Xr wctomb 3 .Sh STANDARDS The .Fn mbtowc function conforms to .St -isoC-99 .