#!/usr/bin/perl -w

use Socket;
use CGI qw/:standard/;

$my_ip = $ENV{'REMOTE_ADDR'};
$ip = inet_aton($my_ip);

$host = gethostbyaddr($ip,AF_INET);
if ($host == "") { $host = $my_ip; } # host not available

print header;
print start_html("Get Hostname");
print "<p>IP: $my_ip\n";
print "<p>Host: $host\n";
print end_html;