xref: /minix3/lib/libc/string/memchr.3 (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)

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.\"     from: @(#)memchr.3	8.1 (Berkeley) 6/4/93
.\"	$NetBSD: memchr.3,v 1.11 2009/04/10 23:24:35 wiz Exp $
.\"
.Dd April 10, 2009
.Dt MEMCHR 3
.Os
.Sh NAME
.Nm memchr ,
.Nm memrchr
.Nd locate byte in byte string
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In string.h
.Ft void *
.Fn memchr "const void *b" "int c" "size_t len"
.Ft void *
.Fn memrchr "const void *b" "int c" "size_t len"
.Sh DESCRIPTION
The
.Fn memchr
function
locates the first occurrence of
.Fa c
(converted to an unsigned char)
in string
.Fa b .
The
.Fn memrchr
function
locates the last occurrence of
.Fa c
(converted to an unsigned char)
in string
.Fa b .
.Sh RETURN VALUES
The
.Fn memchr
and
.Fn memrchr
functions
return a pointer to the byte located, or
.Dv NULL
if no such byte exists within
.Fa len
bytes.
.Sh SEE ALSO
.Xr index 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 memchr
function
conforms to
.St -ansiC .