[apple/libc.git] / locale / FreeBSD / mbtowc.3

.\" Copyright (c) 2002-2004 Tim J. Robbins. All rights reserved.
.\" 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: src/lib/libc/locale/mbtowc.3,v 1.5 2007/01/09 00:28:00 imp Exp $
.\"
.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
.In 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.
.Pp
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.
.Pp
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:
.Bl -tag -width Er
.It Bq Er EILSEQ
An invalid multibyte sequence was detected.
.It 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 .
Commit	Line	Data
3d9156a7	1	.\" Copyright (c) 2002-2004 Tim J. Robbins. All rights reserved.
5b2abdfb	2	.\" Copyright (c) 1993
e9ce8d39 A	3	.\" The Regents of the University of California. All rights reserved.
e9ce8d39 A	4	.\"
5b2abdfb	5	.\" This code is derived from software contributed to Berkeley by
3d9156a7	6	.\" Donn Seeley of BSDI.
5b2abdfb	7	.\"
e9ce8d39 A	8	.\" Redistribution and use in source and binary forms, with or without
	9	.\" modification, are permitted provided that the following conditions
	10	.\" are met:
	11	.\" 1. Redistributions of source code must retain the above copyright
	12	.\" notice, this list of conditions and the following disclaimer.
	13	.\" 2. Redistributions in binary form must reproduce the above copyright
	14	.\" notice, this list of conditions and the following disclaimer in the
	15	.\" documentation and/or other materials provided with the distribution.
e9ce8d39 A	16	.\" 4. Neither the name of the University nor the names of its contributors
	17	.\" may be used to endorse or promote products derived from this software
	18	.\" without specific prior written permission.
	19	.\"
	20	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	.\" SUCH DAMAGE.
	31	.\"
3d9156a7 A	32	.\" From @(#)multibyte.3 8.1 (Berkeley) 6/4/93
3d9156a7 A	33	.\" From FreeBSD: src/lib/libc/locale/multibyte.3,v 1.22 2003/11/08 03:23:11 tjr Exp
1f2f436a	34	.\" $FreeBSD: src/lib/libc/locale/mbtowc.3,v 1.5 2007/01/09 00:28:00 imp Exp $
e9ce8d39	35	.\"
3d9156a7 A	36	.Dd April 11, 2004
3d9156a7 A	37	.Dt MBTOWC 3
e9ce8d39 A	38	.Os
e9ce8d39 A	39	.Sh NAME
3d9156a7 A	40	.Nm mbtowc
	41	.Nd convert a character to a wide-character code
	42	.Sh LIBRARY
	43	.Lb libc
e9ce8d39	44	.Sh SYNOPSIS
3d9156a7 A	45	.In stdlib.h
	46	.Ft int
	47	.Fo mbtowc
	48	.Fa "wchar_t * restrict wcharp" "const char * restrict mbchar"
	49	.Fa "size_t nbytes"
	50	.Fc
e9ce8d39 A	51	.Sh DESCRIPTION
e9ce8d39 A	52	The
3d9156a7 A	53	.Fn mbtowc
	54	function converts a multibyte character
	55	.Fa mbchar
	56	into a wide character according to the current conversion state,
	57	and stores the result
	58	in the object pointed to by
	59	.Fa wcharp .
	60	Up to
	61	.Fa nbytes
	62	bytes are examined.
5b2abdfb	63	.Pp
3d9156a7 A	64	A call with a null
	65	.Fa mbchar
	66	pointer returns nonzero if the current encoding requires shift states,
	67	zero otherwise;
	68	if shift states are required, the shift state is reset to the initial state.
	69	.Sh RETURN VALUES
	70	If
	71	.Fa mbchar
	72	is
	73	.Dv NULL ,
	74	the
	75	.Fn mbtowc
	76	function returns nonzero if shift states are supported,
	77	zero otherwise.
5b2abdfb	78	.Pp
3d9156a7 A	79	Otherwise, if
	80	.Fa mbchar
	81	is not a null pointer,
	82	.Fn mbtowc
	83	either returns 0 if
	84	.Fa mbchar
	85	represents the null wide character, or returns
	86	the number of bytes processed in
	87	.Fa mbchar ,
	88	or returns \-1 if no multibyte character
	89	could be recognized or converted.
	90	In this case,
	91	.Fn mbtowc Ns 's
	92	internal conversion state is undefined.
	93	.Sh ERRORS
	94	The
	95	.Fn mbtowc
	96	function will fail if:
	97	.Bl -tag -width Er
	98	.It Bq Er EILSEQ
	99	An invalid multibyte sequence was detected.
	100	.It Bq Er EINVAL
	101	The internal conversion state is invalid.
	102	.El
	103	.Sh SEE ALSO
	104	.Xr btowc 3 ,
	105	.Xr mblen 3 ,
	106	.Xr mbrtowc 3 ,
	107	.Xr mbstowcs 3 ,
	108	.Xr multibyte 3 ,
	109	.Xr wctomb 3
	110	.Sh STANDARDS
	111	The
	112	.Fn mbtowc
	113	function conforms to
	114	.St -isoC-99 .