1.\" $OpenBSD: strsep.3,v 1.7 2000/03/04 22:19:32 aaron Exp $ 2.\" 3.\" Copyright (c) 1990, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Chris Torek. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the University of 20.\" California, Berkeley and its contributors. 21.\" 4. Neither the name of the University nor the names of its contributors 22.\" may be used to endorse or promote products derived from this software 23.\" without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35.\" SUCH DAMAGE. 36.\" 37.\" @(#)strsep.3 8.1 (Berkeley) 6/9/93 38.\" 39.Dd June 9, 1993 40.Dt STRSEP 3 41.Os 42.Sh NAME 43.Nm strsep 44.Nd separate strings 45.Sh SYNOPSIS 46.Fd #include <string.h> 47.Ft char * 48.Fn strsep "char **stringp" "char *delim" 49.Sh DESCRIPTION 50The 51.Fn strsep 52function locates, in the string referenced by 53.Fa *stringp , 54the first occurrence of any character in the string 55.Fa delim 56(or the terminating 57.Ql \e0 58character) and replaces it with a 59.Ql \e0 . 60The location of the next character after the delimiter character 61(or 62.Dv NULL , 63if the end of the string was reached) is stored in 64.Fa *stringp . 65The original value of 66.Fa *stringp 67is returned. 68.Pp 69An 70.Dq empty 71field, i.e., one caused by two adjacent delimiter characters, 72can be detected by comparing the location referenced by the pointer returned 73by 74.Fn strsep 75to 76.Ql \e0 . 77.Pp 78If 79.Fa *stringp 80is initially 81.Dv NULL , 82.Fn strsep 83returns 84.Dv NULL . 85.Sh EXAMPLES 86The following uses 87.Fn strsep 88to parse a string, containing tokens delimited by whitespace, into an 89argument vector: 90.Bd -literal -offset indent 91char **ap, *argv[10], *inputstring; 92 93for (ap = argv; (*ap = strsep(&inputstring, " \et")) != NULL;) 94 if (**ap != '\e0') 95 ++ap; 96.Ed 97.Sh HISTORY 98The 99.Fn strsep 100function 101is intended as a replacement for the 102.Fn strtok 103function. 104While the 105.Fn strtok 106function should be preferred for portability reasons (it conforms to 107.St -ansiC ) 108it is unable to handle empty fields, i.e., detect fields delimited by 109two adjacent delimiter characters, or to be used for more than a single 110string at a time. 111The 112.Fn strsep 113function first appeared in 114.Bx 4.4 . 115