NetBSD/lib/libc/string/strcmp.3

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.\"     from: @(#)strcmp.3	8.1 (Berkeley) 6/4/93
.\"	$NetBSD: strcmp.3,v 1.13 2006/10/16 08:48:45 wiz Exp $
.\"
.Dd June 4, 1993
.Dt STRCMP 3
.Os
.Sh NAME
.Nm strcmp ,
.Nm strncmp
.Nd compare strings
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In string.h
.Ft int
.Fn strcmp "const char *s1" "const char *s2"
.Ft int
.Fn strncmp "const char *s1" "const char *s2" "size_t len"
.Sh DESCRIPTION
The
.Fn strcmp
and
.Fn strncmp
functions
lexicographically compare the nul-terminated strings
.Fa s1
and
.Fa s2 .
.Sh RETURN VALUES
The
.Fn strcmp
and
.Fn strncmp
return an integer greater than, equal to, or less than 0, according
to whether the string
.Fa s1
is greater than, equal to, or less than the string
.Fa s2 .
The comparison is done using unsigned characters, so that
.Ql \e200
is greater than
.Ql \e0 .
.Pp
The
.Fn strncmp
compares not more than
.Fa len
characters.
.Sh SEE ALSO
.Xr bcmp 3 ,
.Xr memcmp 3 ,
.Xr strcasecmp 3 ,
.Xr strcoll 3 ,
.Xr strxfrm 3
.Sh STANDARDS
The
.Fn strcmp
and
.Fn strncmp
functions
conform to
.St -ansiC .
.Sh NOTES
If
.Fa len
is zero
.Fn strncmp
returns always 0.