/ 
Net-Nslookup-1.07
River stage one • 2 direct dependents • 2 total dependents
/ Net::Nslookup

NAME

Net::Nslookup - Provide nslookup(1)-like capabilities

ABSTRACT

Net::Nslookup provides the capabilities of the standard UNIX command line tool nslookup(1). Net::DNS is a wonderful and full featured module, but quite often, all you need is `nslookup $host`. This module provides that functionality.

SYNOPSIS

use Net::Nslookup;
my @addrs = nslookup $host;

my @mx = nslookup(qtype => "MX", domain => "perl.org");

DESCRIPTION

Net::Nslookup exports a single function, called nslookup. nslookup can be used to retrieve A, PTR, CNAME, MX, and NS records.

my $a  = nslookup(host => "use.perl.org", type => "A");

my @mx = nslookup(domain => "perl.org", type => "MX");

my @ns = nslookup(domain => "perl.org", type => "NS");

nslookup takes a hash of options, one of which should be ``term'', and performs a DNS lookup on that term. The type of lookup is determined by the ``type'' (or ``qtype'') argument.

If only a single argument is passed in, the type defaults to ``A'', that is, a normal A record lookup.

If nslookup is called in a list context, and there is more than one address, an array is returned. If nslookup is called in a scalar context, and there is more than one address, nslookup returns the first address. If there is only one address returned (as is usually the case), then, naturally, it will be the only one returned, regardless of the calling context.

``domain'' and ``host'' are synonyms for ``term'', and can be used to make client code more readable. For example, use ``domain'' when getting NS records, and use ``host'' for A records; both do the same thing.

CONTROLLING SEARCH DOMAINS

Similar to nslookup, Net::Nslookup will try to complete host names that do no appear to be fully qualified. There are three ways to specify a search path: first, by passing arguments to the import() method (called when the module is used):

use Net::Nslookup qw(perl.org perl.com);

There can be as many domains as you need; they are searched in order, and the search stops as soon as a match is found.

The second way to set a search path is by setting the environment variable LOCALDOMAIN to a space-separated list of domains; see resolv.conf(5) for details.

Finally, ``search'' or ``domain'' entries in /etc/resolv.conf are honored, using the same rules as nslookup. The man page for resolv.conf specifies that the last occurance of either domain or search is the one that is used; search can be a space-separated list of domains, similar to the LOCALDOMAIN environment variable.

DEBUGGING

Set $Net::Nslookup::DEBUG to a true value to get debugging messages carped to STDERR.

FUTURE DIRECTIONS

Eventually, this module should be able to work without having Net::DNS installed; currently, Net::Nslookup's functionality is dependent upon that module.

TODO

  • Support for TXT and SOA records.

AUTHOR

darren chamberlain <darren@cpan.org>