1.\" Copyright (c) 1988, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 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. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)strtok.3 8.2 (Berkeley) 2/3/94 37.\" 38.Dd February 3, 1994 39.Dt STRTOK 3 40.Os BSD 3 41.Sh NAME 42.Nm strtok 43.Nd string tokens 44.Sh SYNOPSIS 45.Fd #include <string.h> 46.Ft char * 47.Fn strtok "char *str" "const char *sep" 48.Sh DESCRIPTION 49.Bf -symbolic 50This interface is obsoleted by strsep(3). 51.Ef 52.Pp 53The 54.Fn strtok 55function 56is used to isolate sequential tokens in a null-terminated string, 57.Fa str . 58These tokens are separated in the string by at least one of the 59characters in 60.Fa sep . 61The first time that 62.Fn strtok 63is called, 64.Fa str 65should be specified; subsequent calls, wishing to obtain further tokens 66from the same string, should pass a null pointer instead. 67The separator string, 68.Fa sep , 69must be supplied each time, and may change between calls. 70.Pp 71The 72.Fn strtok 73function 74returns a pointer to the beginning of each subsequent token in the string, 75after replacing the token itself with a 76.Dv NUL 77character. 78When no more tokens remain, a null pointer is returned. 79.Sh SEE ALSO 80.Xr index 3 , 81.Xr memchr 3 , 82.Xr rindex 3 , 83.Xr strchr 3 , 84.Xr strcspn 3 , 85.Xr strpbrk 3 , 86.Xr strrchr 3 , 87.Xr strsep 3 , 88.Xr strspn 3 , 89.Xr strstr 3 90.Sh STANDARDS 91The 92.Fn strtok 93function 94conforms to 95.St -ansiC . 96.Sh BUGS 97There is no way to get tokens from multiple strings simultaneously. 98.Pp 99The System V 100.Fn strtok , 101if handed a string containing only delimiter characters, 102will not alter the next starting point, so that a call to 103.Fn strtok 104with a different (or empty) delimiter string 105may return a 106.Pf non- Dv NULL 107value. 108Since this implementation always alters the next starting point, 109such a sequence of calls would always return 110.Dv NULL . 111