Re: hostname from ip

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)

Comment on Re: hostname from ip Download Code

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Re:x2 hostname from ip (use gethostbyaddr) by grinder (Bishop) on Oct 02, 2003 at 15:19 UTC
Far too complex! `#! /usr/bin/perl -w use strict; use Socket; for( @ARGV ) { if( my $host = gethostbyaddr( inet_aton($_), AF_INET )) { print "$_ is $host\n"; } else { print "$_ NXDOMAIN\n"; } }` [download] Works on my machine :) Note that this will return one record. If you are doing funky things with multiple A or PTR records it might miss the information you're interested in. In which case the Net::DNS module will let you iterate through the RR set. Otherwise it's overkill.	[reply] [d/l]

Replies are listed 'Best First'.

Re:x2 hostname from ip (use gethostbyaddr)
by grinder (Bishop) on Oct 02, 2003 at 15:19 UTC

Far too complex!

#! /usr/bin/perl -w

use strict;
use Socket;

for( @ARGV ) {
   if( my $host = gethostbyaddr( inet_aton($_), AF_INET )) {
        print "$_ is $host\n";
    }
    else {
        print "$_ NXDOMAIN\n";
    }
}
[download]

Works on my machine :)

Note that this will return one record. If you are doing funky things with multiple A or PTR records it might miss the information you're interested in. In which case the Net::DNS module will let you iterate through the RR set. Otherwise it's overkill.

[reply]
[d/l]