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 1.10.2.8 2001/12/14 18:33:59 ru Exp $ 52.\" $DragonFly: src/lib/libc/string/strtok.3,v 1.2 2003/06/17 04:26:47 dillon Exp $ 53.\" 54.Dd November 27, 1998 55.Dt STRTOK 3 56.Os 57.Sh NAME 58.Nm strtok , strtok_r 59.Nd string tokens 60.Sh LIBRARY 61.Lb libc 62.Sh SYNOPSIS 63.In string.h 64.Ft char * 65.Fn strtok "char *str" "const char *sep" 66.Ft char * 67.Fn strtok_r "char *str" "const char *sep" "char **last" 68.Sh DESCRIPTION 69.Bf -symbolic 70This interface is obsoleted by 71.Xr strsep 3 . 72.Ef 73.Pp 74The 75.Fn strtok 76function 77is used to isolate sequential tokens in a null-terminated string, 78.Fa str . 79These tokens are separated in the string by at least one of the 80characters in 81.Fa sep . 82The first time that 83.Fn strtok 84is called, 85.Fa str 86should be specified; subsequent calls, wishing to obtain further tokens 87from the same string, should pass a null pointer instead. 88The separator string, 89.Fa sep , 90must be supplied each time, and may change between calls. 91.Pp 92The implementation will behave as if no library function calls 93.Fn strtok . 94.Pp 95The 96.Fn strtok_r 97function is a reentrant version of 98.Fn strtok . 99The context pointer 100.Fa last 101must be provided on each call. 102.Fn strtok_r 103may also be used to nest two parsing loops within one another, as 104long as separate context pointers are used. 105.Pp 106The 107.Fn strtok 108and 109.Fn strtok_r 110functions 111return a pointer to the beginning of each subsequent token in the string, 112after replacing the token itself with a 113.Dv NUL 114character. 115When no more tokens remain, a null pointer is returned. 116.Sh EXAMPLES 117The following uses 118.Fn strtok_r 119to parse two strings using separate contexts: 120.Bd -literal 121char test[80], blah[80]; 122char *sep = "\e\e/:;=-"; 123char *word, *phrase, *brkt, *brkb; 124 125strcpy(test, "This;is.a:test:of=the/string\e\etokenizer-function."); 126 127for (word = strtok_r(test, sep, &brkt); 128 word; 129 word = strtok_r(NULL, sep, &brkt)) 130{ 131 strcpy(blah, "blah:blat:blab:blag"); 132 133 for (phrase = strtok_r(blah, sep, &brkb); 134 phrase; 135 phrase = strtok_r(NULL, sep, &brkb)) 136 { 137 printf("So far we're at %s:%s\en", word, phrase); 138 } 139} 140.Ed 141.Sh SEE ALSO 142.Xr memchr 3 , 143.Xr strchr 3 , 144.Xr strcspn 3 , 145.Xr strpbrk 3 , 146.Xr strrchr 3 , 147.Xr strsep 3 , 148.Xr strspn 3 , 149.Xr strstr 3 150.Sh STANDARDS 151The 152.Fn strtok 153function 154conforms to 155.St -isoC . 156.Sh BUGS 157The System V 158.Fn strtok , 159if handed a string containing only delimiter characters, 160will not alter the next starting point, so that a call to 161.Fn strtok 162with a different (or empty) delimiter string 163may return a 164.Pf non- Dv NULL 165value. 166Since this implementation always alters the next starting point, 167such a sequence of calls would always return 168.Dv NULL . 169.Sh AUTHORS 170.An Wes Peters , 171Softweyr LLC: 172.Aq wes@softweyr.com 173.Pp 174Based on the 175.Fx 3.0 176implementation. 177