0    #!/usr/bin/perl

1    use strict;
2    my @SUFFIX  = qw(com net org);

3    # feed list of words you want to check for
4    while (<>) {
5      chomp;
6      for my $suffix (@SUFFIX) {
7        my $name = "$_.$suffix";
8        my $status = do_lookup($name);
9        print "$name: $status\n";
10      }
11    }

12    sub do_lookup {
13      my $name = shift;

14      # try the DNS first (faster)
15      my $dns = `nslookup -type=NS $name 2>/dev/null`;
16      return "used by $1" if $dns =~ /nameserver = (\S+)$/m;

17      # try whois
18      my $whois = `whois $name`;
19      return "registered to $1" if $whois =~ /Name Server:\s+(\S+)/;

20      # otherwise not found
21      return 'available';
22    }