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

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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 module, which also comes with perl.

use Socket;

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



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