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	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	.\"
	50	.\" @(#)strtok.3 8.2 (Berkeley) 2/3/94
	51	.\" $FreeBSD: src/lib/libc/string/strtok.3,v 1.24 2002/12/18 12:45:11 ru Exp $
	52	.\"
	53	.Dd November 27, 1998
	54	.Dt STRTOK 3
	55	.Os
	56	.Sh NAME
	57	.Nm strtok , strtok_r
	58	.Nd string tokens
	59	.Sh LIBRARY
	60	.Lb libc
	61	.Sh SYNOPSIS
	62	.In string.h
	63	.Ft char *
	64	.Fo strtok
	65	.Fa "char *restrict str"
	66	.Fa "const char *restrict sep"
	67	.Fc
	68	.Ft char *
	69	.Fo strtok_r
	70	.Fa "char *restrict str"
	71	.Fa "const char *restrict sep"
	72	.Fa "char **restrict lasts"
	73	.Fc
	74	.Sh DESCRIPTION
	75	.Bf -symbolic
	76	This interface is obsoleted by
	77	.Xr strsep 3 .
	78	.Ef
	79	.Pp
	80	The
	81	.Fn strtok
	82	function
	83	is used to isolate sequential tokens in a null-terminated string,
	84	.Fa str .
	85	These tokens are separated in the string by at least one of the
	86	characters in
	87	.Fa sep .
	88	The first time that
	89	.Fn strtok
	90	is called,
	91	.Fa str
	92	should be specified; subsequent calls, wishing to obtain further tokens
	93	from the same string, should pass a null pointer instead.
	94	The separator string,
	95	.Fa sep ,
	96	must be supplied each time, and may change between calls.
	97	.Pp
	98	The implementation will behave as if no library function calls
	99	.Fn strtok .
	100	.Pp
	101	The
	102	.Fn strtok_r
	103	function is a reentrant version of
	104	.Fn strtok .
	105	The context pointer
	106	.Fa last
	107	must be provided on each call.
	108	The
	109	.Fn strtok_r
	110	function
	111	may also be used to nest two parsing loops within one another, as
	112	long as separate context pointers are used.
	113	.Pp
	114	The
	115	.Fn strtok
	116	and
	117	.Fn strtok_r
	118	functions
	119	return a pointer to the beginning of each subsequent token in the string,
	120	after replacing the token itself with a
	121	.Dv NUL
	122	character.
	123	When no more tokens remain, a null pointer is returned.
	124	.Sh EXAMPLES
	125	The following uses
	126	.Fn strtok_r
	127	to parse two strings using separate contexts:
	128	.Bd -literal
	129	char test[80], blah[80];
	130	char *sep = "\e\e/:;=-";
	131	char word, phrase, brkt, brkb;
	132
	133	strcpy(test, "This;is.a:test:of=the/string\e\etokenizer-function.");
	134
	135	for (word = strtok_r(test, sep, &brkt);
	136	word;
	137	word = strtok_r(NULL, sep, &brkt))
	138	{
	139	strcpy(blah, "blah:blat:blab:blag");
	140
	141	for (phrase = strtok_r(blah, sep, &brkb);
	142	phrase;
	143	phrase = strtok_r(NULL, sep, &brkb))
	144	{
	145	printf("So far we're at %s:%s\en", word, phrase);
	146	}
	147	}
	148	.Ed
	149	.Sh SEE ALSO
	150	.Xr memchr 3 ,
	151	.Xr strchr 3 ,
	152	.Xr strcspn 3 ,
	153	.Xr strpbrk 3 ,
	154	.Xr strrchr 3 ,
	155	.Xr strsep 3 ,
	156	.Xr strspn 3 ,
	157	.Xr strstr 3 ,
	158	.Xr wcstok 3
	159	.Sh STANDARDS
	160	The
	161	.Fn strtok
	162	function
	163	conforms to
	164	.St -isoC .
	165	.Sh BUGS
	166	The System V
	167	.Fn strtok ,
	168	if handed a string containing only delimiter characters,
	169	will not alter the next starting point, so that a call to
	170	.Fn strtok
	171	with a different (or empty) delimiter string
	172	may return a
	173	.Pf non- Dv NULL
	174	value.
	175	Since this implementation always alters the next starting point,
	176	such a sequence of calls would always return
	177	.Dv NULL .
	178	.Sh AUTHORS
	179	.An Wes Peters ,
	180	Softweyr LLC:
	181	.Aq wes@softweyr.com
	182	.Pp
	183	Based on the
	184	.Fx 3.0
	185	implementation.