#!/usr/local/bin/perl
#
# This script does a reverse address lookup, returning
# a host name when given an IP address.  It uses the 
# gethostbyaddr function call, which means it will use 
# whatever name resolution method the host running the 
# program uses.  This is meant to provide a more easily 
# parsed format for output than nslookup provides.
#
# Andy Welter
# www.the-welters.com
# January 16, 2001
#
use Socket;
$addr=$ARGV[0];
$hostname=gethostbyaddr(inet_aton ($addr), AF_INET);
if ( $hostname ) {
	print "$hostname\n";
} else {
	exit 1;
};