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.\"     from: @(#)strcasecmp.3	8.1 (Berkeley) 6/9/93
.\"	$NetBSD: strcasecmp.3,v 1.21 2016/07/13 09:05:16 abhinav Exp $
.\"
.Dd July 11, 2016
.Dt STRCASECMP 3
.Os
.Sh NAME
.Nm strcasecmp ,
.Nm strncasecmp
.Nd compare strings, ignoring case
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In strings.h
.Ft int
.Fn strcasecmp "const char *s1" "const char *s2"
.Ft int
.Fn strncasecmp "const char *s1" "const char *s2" "size_t len"
.Sh DESCRIPTION
The
.Fn strcasecmp
and
.Fn strncasecmp
functions
compare the nul-terminated strings
.Fa s1
and
.Fa s2
and return an integer greater than, equal to, or less than 0,
according to whether
.Fa s1
is lexicographically greater than, equal to, or less than
.Fa s2
after translation of each corresponding character to lower-case.
The strings themselves are not modified.
The comparison is done using unsigned characters, so that
.Sq Li \e200
is greater than
.Ql \e0 .
.Pp
The
.Fn strncasecmp
function
compares at most
.Fa len
characters.
.Sh SEE ALSO
.Xr bcmp 3 ,
.Xr memcmp 3 ,
.Xr strcmp 3 ,
.Xr strcoll 3 ,
.Xr strxfrm 3
.Sh STANDARDS
The
.Fn strcasecmp
and
.Fn strncasecmp
functions conform to
.St -p1003.1-2001 .
.Sh HISTORY
The
.Fn strcasecmp
and
.Fn strncasecmp
functions first appeared in
.Bx 4.4 .
.Sh NOTES
If
.Fa len
is 0
.Fn strncasecmp
always returns 0.