[apple/libc.git] / string / FreeBSD / wcstok.3

.\" Copyright (c) 1998 Softweyr LLC.  All rights reserved.
.\"
.\" strtok_r, from Berkeley strtok
.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
.\"
.\" Copyright (c) 1988, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
.\"
.\" 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
.\"    notices, this list of conditions and the following disclaimer.
.\"
.\" 2. Redistributions in binary form must reproduce the above
.\"    copyright notices, this list of conditions and the following
.\"    disclaimer in the documentation and/or other materials provided
.\"    with the distribution.
.\"
.\" 3. All advertising materials mentioning features or use of this
.\"    software must display the following acknowledgement:
.\"
.\"	This product includes software developed by Softweyr LLC, the
.\"      University of California, Berkeley, and its contributors.
.\"
.\" 4. Neither the name of Softweyr LLC, 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 SOFTWEYR LLC, 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 SOFTWEYR LLC, 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.
.\"
.\" $FreeBSD: src/lib/libc/string/wcstok.3,v 1.4 2002/10/15 09:49:54 tjr Exp $
.\"
.Dd October 3, 2002
.Dt WCSTOK 3
.Os
.Sh NAME
.Nm wcstok
.Nd split wide-character string into tokens
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In wchar.h
.Ft wchar_t *
.Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
.Sh DESCRIPTION
The
.Fn wcstok
function
is used to isolate sequential tokens in a null-terminated wide character
string,
.Fa str .
These tokens are separated in the string by at least one of the
characters in
.Fa sep .
The first time that
.Fn wcstok
is called,
.Fa str
should be specified; subsequent calls, wishing to obtain further tokens
from the same string, should pass a null pointer instead.
The separator string,
.Fa sep ,
must be supplied each time, and may change between calls.
The context pointer
.Fa last
must be provided on each call.
.Pp
The
.Fn wcstok
function is the wide character counterpart of the
.Fn strtok_r
function.
.Sh RETURN VALUES
The
.Fn wcstok
function
returns a pointer to the beginning of each subsequent token in the string,
after replacing the token itself with a null wide character (L'\e0').
When no more tokens remain, a null pointer is returned.
.Sh EXAMPLES
The following code fragment splits a wide character string on
.Tn ASCII
space, tab and newline characters and writes the tokens to
standard output:
.Bd -literal -offset indent
const wchar_t *seps = L" \et\en";
wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";

for (tok = wcstok(text, seps, &last); tok != NULL;
    tok = wcstok(NULL, seps, &last))
	wprintf(L"%ls\en", tok);
.Ed
.Sh COMPATIBILITY
Some early implementations of
.Fn wcstok
omit the
context pointer argument,
.Fa last ,
and maintain state across calls in a static variable like
.Fn strtok
does.
.Sh SEE ALSO
.Xr strtok 3 ,
.Xr wcschr 3 ,
.Xr wcscspn 3 ,
.Xr wcspbrk 3 ,
.Xr wcsrchr 3 ,
.Xr wcsspn 3
.Sh STANDARDS
The
.Fn wcstok
function
conforms to
.St -isoC-99 .
Commit	Line	Data
5b2abdfb A	1	.\" Copyright (c) 1998 Softweyr LLC. All rights reserved.
	2	.\"
	3	.\" strtok_r, from Berkeley strtok
	4	.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
	5	.\"
	6	.\" Copyright (c) 1988, 1991, 1993
	7	.\" The Regents of the University of California. All rights reserved.
	8	.\"
	9	.\" This code is derived from software contributed to Berkeley by
	10	.\" the American National Standards Committee X3, on Information
	11	.\" Processing Systems.
	12	.\"
	13	.\" Redistribution and use in source and binary forms, with or without
	14	.\" modification, are permitted provided that the following conditions
	15	.\" are met:
	16	.\"
	17	.\" 1. Redistributions of source code must retain the above copyright
	18	.\" notices, this list of conditions and the following disclaimer.
	19	.\"
	20	.\" 2. Redistributions in binary form must reproduce the above
	21	.\" copyright notices, this list of conditions and the following
	22	.\" disclaimer in the documentation and/or other materials provided
	23	.\" with the distribution.
	24	.\"
	25	.\" 3. All advertising materials mentioning features or use of this
	26	.\" software must display the following acknowledgement:
	27	.\"
	28	.\" This product includes software developed by Softweyr LLC, the
	29	.\" University of California, Berkeley, and its contributors.
	30	.\"
	31	.\" 4. Neither the name of Softweyr LLC, the University nor the names
	32	.\" of its contributors may be used to endorse or promote products
	33	.\" derived from this software without specific prior written
	34	.\" permission.
	35	.\"
	36	.\" THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS AND
	37	.\" CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
	38	.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	39	.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	40	.\" DISCLAIMED. IN NO EVENT SHALL SOFTWEYR LLC, THE REGENTS, OR
	41	.\" CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	42	.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	43	.\" LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	44	.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	45	.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	46	.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	47	.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	48	.\" SUCH DAMAGE.
	49	.\"
9385eb3d	50	.\" $FreeBSD: src/lib/libc/string/wcstok.3,v 1.4 2002/10/15 09:49:54 tjr Exp $
5b2abdfb	51	.\"
9385eb3d A	52	.Dd October 3, 2002
9385eb3d A	53	.Dt WCSTOK 3
5b2abdfb A	54	.Os
5b2abdfb A	55	.Sh NAME
9385eb3d A	56	.Nm wcstok
9385eb3d A	57	.Nd split wide-character string into tokens
5b2abdfb A	58	.Sh LIBRARY
	59	.Lb libc
	60	.Sh SYNOPSIS
9385eb3d A	61	.In wchar.h
	62	.Ft wchar_t *
	63	.Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
5b2abdfb	64	.Sh DESCRIPTION
5b2abdfb	65	The
9385eb3d	66	.Fn wcstok
5b2abdfb	67	function
9385eb3d A	68	is used to isolate sequential tokens in a null-terminated wide character
9385eb3d A	69	string,
5b2abdfb A	70	.Fa str .
	71	These tokens are separated in the string by at least one of the
	72	characters in
	73	.Fa sep .
	74	The first time that
9385eb3d	75	.Fn wcstok
5b2abdfb A	76	is called,
	77	.Fa str
	78	should be specified; subsequent calls, wishing to obtain further tokens
	79	from the same string, should pass a null pointer instead.
	80	The separator string,
	81	.Fa sep ,
	82	must be supplied each time, and may change between calls.
5b2abdfb A	83	The context pointer
	84	.Fa last
	85	must be provided on each call.
5b2abdfb A	86	.Pp
5b2abdfb A	87	The
9385eb3d A	88	.Fn wcstok
9385eb3d A	89	function is the wide character counterpart of the
5b2abdfb	90	.Fn strtok_r
9385eb3d A	91	function.
	92	.Sh RETURN VALUES
	93	The
	94	.Fn wcstok
	95	function
	96	returns a pointer to the beginning of each subsequent token in the string,
	97	after replacing the token itself with a null wide character (L'\e0').
5b2abdfb A	98	When no more tokens remain, a null pointer is returned.
5b2abdfb A	99	.Sh EXAMPLES
9385eb3d A	100	The following code fragment splits a wide character string on
	101	.Tn ASCII
	102	space, tab and newline characters and writes the tokens to
	103	standard output:
	104	.Bd -literal -offset indent
	105	const wchar_t *seps = L" \et\en";
	106	wchar_t last, tok, text[] = L" \enone\ettwo\et\etthree \en";
5b2abdfb	107
9385eb3d A	108	for (tok = wcstok(text, seps, &last); tok != NULL;
	109	tok = wcstok(NULL, seps, &last))
	110	wprintf(L"%ls\en", tok);
5b2abdfb	111	.Ed
9385eb3d A	112	.Sh COMPATIBILITY
	113	Some early implementations of
	114	.Fn wcstok
	115	omit the
	116	context pointer argument,
	117	.Fa last ,
	118	and maintain state across calls in a static variable like
	119	.Fn strtok
	120	does.
5b2abdfb	121	.Sh SEE ALSO
9385eb3d A	122	.Xr strtok 3 ,
	123	.Xr wcschr 3 ,
	124	.Xr wcscspn 3 ,
	125	.Xr wcspbrk 3 ,
	126	.Xr wcsrchr 3 ,
	127	.Xr wcsspn 3
5b2abdfb A	128	.Sh STANDARDS
5b2abdfb A	129	The
9385eb3d	130	.Fn wcstok
5b2abdfb A	131	function
5b2abdfb A	132	conforms to
9385eb3d	133	.St -isoC-99 .