#!/usr/local/bin/perl -w
#
# Copyright (C) 2004, 2005 Philipp Benner
#
# This file is part of UpdateDD - http://updatedd.philipp-benner.de.
#
# UpdateDD is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# any later version.
#
# UpdateDD is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with UpdateDD; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

use strict;

my $ipv4_rex = qr/(?:\d{1,3}\.){3}\d{1,3}/imosx;

sub print_usage($) {

    my $file = shift;

    print($file "Usage: interface.pl IFNAME\n");

}

if(@ARGV != 1) {
    print("wrong usage\n");
    print("See `interface.pl --help' for more information.\n");
    exit(1);
}
if($ARGV[0] eq "--help") {
    print_usage(\*STDOUT);
    exit(0);
}

my $output = `ifconfig $ARGV[0]`;
if($output =~ /inet \w+:($ipv4_rex)/) {
    print("$1\n");
} elsif($output =~ /inet ($ipv4_rex)/) {
    print("$1\n");
}