#!/usr/bin/perl
use strict; 
use warnings;
use Net::Ping;

my $target_name = 'www.bbc.co.uk';
# The name doesn't always resolve to the same IP, so we pick one
# and stick with it

my (undef, undef, $target_ip) = Net::Ping->new("icmp")
                                         ->ping($target_name);

for my $ttl (1..30){
  # Only way to change the ttl is at object construction time
  # ALL the intermediate parameters are required; skipping or using
  # 'undef' doesn't work
  my $p = Net::Ping->new("icmp", 0.5, 0, 0, 0, $ttl);
  $p->ping($target_ip);
  # Not all pings will return a 'from_ip', so initialise it here
  my $from_ip = '*.*.*.*';
  # If the intermediate host returned an IP, it will be in the
  # undocumented 'from_ip' element of the object
  $from_ip = join('.',unpack('C4', $p->{from_ip})) if $p->{from_ip};
  print "$ttl \t $from_ip \n";
  # If the 'from_ip' is the same as the target, we're done
  last if $from_ip eq $target_ip;
}

0;

__END__