#!/usr/bin/perl
 
use strict;
use LWP::Simple;
use Sys::Syslog qw( :DEFAULT setlogsock);

my $dir = "/root/script/";
my $emailadd = "your\@email.com";
my $fromadd = "ipwatch\@yourmachine"; 

chdir $dir;

my $current_ip = get('http://www.chisono.it/ip.asp') || logit('err', "Cannot retrieve the IP address: $!\n"); 

my ($a1, $a2, $a3, $a4) = split /\./, $current_ip;

open FILE, "myip.txt" or logit('err', "Cannot open the file: $!\n");

my $readip = <FILE>;
my ($b1, $b2, $b3, $b4) = split /\./, $readip;
 
if ($readip eq $current_ip) {
       logit('info', "Address not changed\n");
} else {
       logit('info', "Address changed: old IP: $readip ; New IP: $current_ip\n");
 
       getstore('http://www.chisono.it/ip.asp', 'myip.txt');
 
       system("mailx -s \"IP changed!\" -a \"From: IPWatch <$fromadd>\" $emailadd < myip.txt") || logit('err', "Cannot send the email!\n");
}

sub logit {
   my ($priority, $msg) = @_; 
   return 0 unless ($priority =~ /info|err|debug/);
   setlogsock('unix');
   openlog($0, 'pid,cons', 'user');
   syslog($priority, $msg);
   closelog();
   return 1;
}