.\"	$OpenBSD: strchr.3,v 1.10 2011/07/25 00:38:53 schwarze Exp $
.\"
.\" Copyright (c) 1990, 1991 The Regents of the University of California.
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.\" This code is derived from software contributed to Berkeley by
.\" Chris Torek and the American National Standards Committee X3,
.\" on Information Processing Systems.
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.\" modification, are permitted provided that the following conditions
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.Dd $Mdocdate: July 25 2011 $
.Dt STRCHR 3
.Os
.Sh NAME
.Nm strchr ,
.Nm index
.Nd locate first occurrence of a character in a string
.Sh SYNOPSIS
.Fd #include <string.h>
.Ft char *
.Fn strchr "const char *s" "int c"
.Ft char *
.Fn index "const char *s" "int c"
.Sh DESCRIPTION
The
.Fn strchr
function locates the first occurrence of the character
.Fa c
in the string
.Fa s .
The terminating NUL character is considered part of the string.
If
.Fa c
is
.Ql \e0 ,
.Fn strchr
locates the terminating
.Ql \e0 .
.Pp
The
.Fn index
function is an old synonym for
.Fn strchr .
.Sh RETURN VALUES
The
.Fn strchr
function returns a pointer to the located character or
.Dv NULL
if the character does not appear in the string.
.Sh EXAMPLES
After the following call to
.Fn strchr ,
.Va p
will point to the string
.Qq oobar :
.Bd -literal -offset indent
char *p;
char *s = "foobar";

p = strchr(s, 'o');
.Ed
.Sh SEE ALSO
.Xr memchr 3 ,
.Xr strcspn 3 ,
.Xr strpbrk 3 ,
.Xr strrchr 3 ,
.Xr strsep 3 ,
.Xr strspn 3 ,
.Xr strstr 3 ,
.Xr strtok 3 ,
.Xr wcschr 3
.Sh STANDARDS
The
.Fn strchr
function conforms to
.St -ansiC .
.Pp
The
.Fn index
function is deprecated and shouldn't be used in new code.
.Sh HISTORY
The
.Fn index
function first appeared in
.At v7 .
The
.Fn strchr
function first appeared in
.At III
and was reimplemented for
.Bx 4.3 Tahoe .