1.\" $OpenBSD: strchr.3,v 1.11 2013/06/05 03:39:23 tedu Exp $ 2.\" 3.\" Copyright (c) 1990, 1991 The Regents of the University of California. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Chris Torek and the American National Standards Committee X3, 8.\" on Information Processing Systems. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.Dd $Mdocdate: June 5 2013 $ 35.Dt STRCHR 3 36.Os 37.Sh NAME 38.Nm strchr , 39.Nm index 40.Nd locate first occurrence of a character in a string 41.Sh SYNOPSIS 42.In string.h 43.Ft char * 44.Fn strchr "const char *s" "int c" 45.Ft char * 46.Fn index "const char *s" "int c" 47.Sh DESCRIPTION 48The 49.Fn strchr 50function locates the first occurrence of the character 51.Fa c 52in the string 53.Fa s . 54The terminating NUL character is considered part of the string. 55If 56.Fa c 57is 58.Ql \e0 , 59.Fn strchr 60locates the terminating 61.Ql \e0 . 62.Pp 63The 64.Fn index 65function is an old synonym for 66.Fn strchr . 67.Sh RETURN VALUES 68The 69.Fn strchr 70function returns a pointer to the located character or 71.Dv NULL 72if the character does not appear in the string. 73.Sh EXAMPLES 74After the following call to 75.Fn strchr , 76.Va p 77will point to the string 78.Qq oobar : 79.Bd -literal -offset indent 80char *p; 81char *s = "foobar"; 82 83p = strchr(s, 'o'); 84.Ed 85.Sh SEE ALSO 86.Xr memchr 3 , 87.Xr strcspn 3 , 88.Xr strpbrk 3 , 89.Xr strrchr 3 , 90.Xr strsep 3 , 91.Xr strspn 3 , 92.Xr strstr 3 , 93.Xr strtok 3 , 94.Xr wcschr 3 95.Sh STANDARDS 96The 97.Fn strchr 98function conforms to 99.St -ansiC . 100.Pp 101The 102.Fn index 103function is deprecated and shouldn't be used in new code. 104.Sh HISTORY 105The 106.Fn index 107function first appeared in 108.At v7 . 109The 110.Fn strchr 111function first appeared in 112.At III 113and was reimplemented for 114.Bx 4.3 Tahoe . 115