paranoid times has asked for the wisdom of the Perl Monks concerning the following question:

I want to get the system IP address without using outside applications. Right now my code looks like this:

$ip=`host $hostname`;
$ip =~ s/$hostname has address //;
chomp $ip;

I would prefer to avoid using "host". I found something called "IP::Authority" and another thing called "Net::Address::IPv4::Local" both looked as though they could do what I wanted, however both caused my script to make errors about not being able to locate it (by the way what are those things with the colins called, tools, modules, something else?). Is there some standard pseudo-universal way of getting an IP address with perl?

Thanks for any help,
Michael

Replies are listed 'Best First'.
Re: Getting the system ip address
by McDarren (Abbot) on Apr 04, 2006 at 23:42 UTC
    perldoc -q hostname tells us: 
           How do I find out my hostname/domainname/IP address?

       The normal way to find your own hostname is to call the `hostna
+me` program.  
While sometimes expedient, this has some problems, such as not knowing
+ whether you've got the 
canonical name or not.  It's one of those tradeoffs of convenience ver
+sus portability.

       The Sys::Hostname module (part of the standard perl distributio
+n) will give you the hostname 
after which you can find out the IP address (assuming you have working
+ DNS) 
with a gethostbyname() call.

           use Socket;
           use Sys::Hostname;
           my $host = hostname();
           my $addr = inet_ntoa(scalar gethostbyname($host || 'localho
+st'));

    [download]

    Cheers,
    Darren :)

[reply]
[d/l]
[select]
      Thank you very much, thats working great.

      Is there any particular way that you reached looking up hostname in perldoc? Or did you arrive at that conclusion from experience?
[reply]
        On a *nix system, I typed "perldoc -q hostname" from the commandline. If you're on Windows (which you don't appear to be), then you can find it all at perldoc.perl.org.

        Apart from the Camel, perldoc is my very best friend - and I'd certainly encourage you to get aquainted with it :)

[reply]
Re: Getting the system ip address
by tirwhan (Abbot) on Apr 05, 2006 at 05:36 UTC
[reply]
[d/l]

Back to Seekers of Perl Wisdom