use perl script to test if the computer is inside corporate intranet

use Socket;
use strict;

if (isIntranet()) {
  print "intranet\n";
} else {
  print "internet\n";
}

sub isIntranet {
  my $intranethost="some.intranet.com"; //any hostname only visible inside intranet
  my $iaddr=gethostbyname($intranethost); 
  return $iaddr;
}