#!/usr/bin/perl -w

my $ip_last_check_file = "/home/thomas/.currentip/ip";
my $ip_now = `curl -s http://checkip.dyndns.org`;
$ip_now =~ s/.*?(\d+\.\d+\.\d+\.\d+).*/$1/s;

open(IP, "<$ip_last_check_file") or die "Cannot open $ip_last_check_file: $!";
my $ip_last_check = <IP>;
close(IP);

if ($ip_now ne $ip_last_check)
{
  open(IP, ">$ip_last_check_file") or die "Cannot open $ip_last_check: $!";
  print IP $ip_now;
  close(IP);
}

exit;