The Perl Cookbook Recipe 17.7 discusses this, but you have to have a SOCKET first. Take a look at Net::DNS and Acme::DNS::Correct. From the docs: 
use strict;
use warnings;
use Net::DNS;
use Acme::DNS::Correct 'sneaky';
use Data::Dumper;

my $res = Net::DNS::Resolver->new;
my $query = $res->search("host.example.com");

if ($query) {
   foreach my $rr ($query->answer) {
      next unless $rr->type eq "A";
      print $rr->address, "\n";
   }
} else {
   warn "query failed: ", $res->errorstring, "\n";
}

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: hostname from ip by jeffa
in thread hostname from ip by Anonymous Monk

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