#/usr/bin/perl -w

use warnings;
use strict;

use Net::DNS; 
my $rr;

  my $res   = Net::DNS::Resolver->new;
  my $query = $res->query("http://www.yahoo.com", "NS");
  
  if ($query) {
      foreach $rr ($query->answer) {
          next unless $rr->type eq "NS";
          print $rr->nsdname, "\n";
      }
  }
  else {
      print "query failed: ", $res->errorstring, "\n";
  }