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.\"     from: @(#)index.3	8.1 (Berkeley) 6/4/93
.\"	$NetBSD: index.3,v 1.15 2012/05/05 21:18:43 dholland Exp $
.\"
.Dd May 5, 2012
.Dt INDEX 3
.Os
.Sh NAME
.Nm index
.Nd locate character in string
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In strings.h
.Ft char *
.Fn index "const char *s" "int c"
.Sh DESCRIPTION
The
.Fn index
function
locates the first character matching
.Fa c
(converted to a
.Em char )
in the nul-terminated string
.Fa s .
.Pp
This function is obsolete.
The equivalent function
.Xr strchr 3
should be used instead.
.Sh RETURN VALUES
A pointer to the character is returned if it is found; otherwise
.Dv NULL
is returned.
If
.Fa c
is '\e0',
.Fn index
locates the terminating '\e0'.
.Sh SEE ALSO
.Xr memchr 3 ,
.Xr rindex 3 ,
.Xr strchr 3 ,
.Xr strcspn 3 ,
.Xr strpbrk 3 ,
.Xr strrchr 3 ,
.Xr strsep 3 ,
.Xr strspn 3 ,
.Xr strstr 3 ,
.Xr strtok 3
.Sh STANDARDS
The
.Fn index
function conforms to
.St -p1003.1-2001 .
The
.St -p1003.1-2004
revision marked it as legacy and recommended the use of
.Xr strchr 3
instead.
The
.St -p1003.1-2008
revision removed
.Fn index
from the specification.
.Sh HISTORY
An
.Fn index
function appeared in
.At v6 .