From: PerlFAQ Server on
This is an excerpt from the latest version perlfaq9.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

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9.23: How do I find out my hostname, domainname, or IP address?

(contributed by brian d foy)

The Net::Domain module, which is part of the standard distribution
starting in perl5.7.3, can get you the fully qualified domain name
(FQDN), the host name, or the domain name.

use Net::Domain qw(hostname hostfqdn hostdomain);

my $host = hostfqdn();

The "Sys::Hostname" module, included in the standard distribution since
perl5.6, can also get the hostname.

use Sys::Hostname;

$host = hostname();

To get the IP address, you can use the "gethostbyname" built-in function
to turn the name into a number. To turn that number into the dotted
octet form (a.b.c.d) that most people expect, use the "inet_ntoa"
function from the <Socket> module, which also comes with perl.

use Socket;

my $address = inet_ntoa(
scalar gethostbyname( $host || 'localhost' )
);



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