1.\" Copyright (c) 1990, 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.\" Chris Torek. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 4. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)strsep.3 8.1 (Berkeley) 6/9/93 32.\" $FreeBSD: src/lib/libc/string/strsep.3,v 1.16 2008/12/05 15:50:59 pjd Exp $ 33.\" $DragonFly: src/lib/libc/string/strsep.3,v 1.2 2003/06/17 04:26:46 dillon Exp $ 34.\" 35.Dd December 5, 2008 36.Dt STRSEP 3 37.Os 38.Sh NAME 39.Nm strsep 40.Nd separate strings 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In string.h 45.Ft char * 46.Fn strsep "char **stringp" "const char *delim" 47.Sh DESCRIPTION 48The 49.Fn strsep 50function locates, in the string referenced by 51.Fa *stringp , 52the first occurrence of any character in the string 53.Fa delim 54(or the terminating 55.Ql \e0 56character) and replaces it with a 57.Ql \e0 . 58The location of the next character after the delimiter character 59(or NULL, if the end of the string was reached) is stored in 60.Fa *stringp . 61The original value of 62.Fa *stringp 63is returned. 64.Pp 65An 66.Dq empty 67field (i.e., a character in the string 68.Fa delim 69occurs as the first character of 70.Fa *stringp ) 71can be detected by comparing the location referenced by the returned pointer 72to 73.Ql \e0 . 74.Pp 75If 76.Fa *stringp 77is initially 78.Dv NULL , 79.Fn strsep 80returns 81.Dv NULL . 82.Sh EXAMPLES 83The following uses 84.Fn strsep 85to parse a string, and prints each token in separate line: 86.Bd -literal -offset indent 87char *token, *string, *tofree; 88 89tofree = string = strdup("abc,def,ghi"); 90assert(string != NULL); 91 92while ((token = strsep(&string, ",")) != NULL) 93 printf("%s\en", token); 94 95free(tofree); 96.Ed 97.Pp 98The following uses 99.Fn strsep 100to parse a string, containing tokens delimited by white space, into an 101argument vector: 102.Bd -literal -offset indent 103char **ap, *argv[10], *inputstring; 104 105for (ap = argv; (*ap = strsep(&inputstring, " \et")) != NULL;) 106 if (**ap != '\e0') 107 if (++ap >= &argv[10]) 108 break; 109.Ed 110.Sh SEE ALSO 111.Xr memchr 3 , 112.Xr strchr 3 , 113.Xr strcspn 3 , 114.Xr strpbrk 3 , 115.Xr strrchr 3 , 116.Xr strspn 3 , 117.Xr strstr 3 , 118.Xr strtok 3 119.Sh HISTORY 120The 121.Fn strsep 122function 123is intended as a replacement for the 124.Fn strtok 125function. 126While the 127.Fn strtok 128function should be preferred for portability reasons (it conforms to 129.St -isoC ) 130it is unable to handle empty fields, i.e., detect fields delimited by 131two adjacent delimiter characters, or to be used for more than a single 132string at a time. 133The 134.Fn strsep 135function first appeared in 136.Bx 4.4 . 137