my $dns = new Net::DNS::Resolver;
$dns->tcp_timeout( 1 );
$dns->udp_timeout( 1 );

my $my_file = $ARGV[0];

open(INFILE, $my_file) || die ("I refuse to open your file!");

my @my_data=<INFILE>;

close(INFILE);

foreach my $line(@my_data) {
	## Parse the file
	chop($line);
	my ($number,$domain)=split(/,/,$line);
	testDns($number,$domain,$dns);
}

sub testDns {
	my ($line_number, $domain_to_test, $default_resolver) = @_;

	my $ns = $default_resolver->query( $domain_to_test, 'NS' );
	if ($ns) {
		foreach my $rr ($ns->answer) {
			if ($rr->type eq "NS") {
				my @auth_nameservers = $rr->nsdname;
				foreach my $auth_nameserver (@auth_nameservers) {
					print "$line_number,$domain_to_test,$auth_nameserver\n";
        	}
		}
	}
	else { print "$line_number,$domain_to_test,error\n"; }
}