finding ethernet interfaces and IPs

[Zebee Johnstone]

I have a machine with more than one ethernet interface, and several
IP's aliased to the interfaces.


And several machines with aliases but only one interface.

So I don't want to hardcode interface names like eth0 into anything.

I want a list of IP addresses on the machine and the interface each IP
lives on.

I've been using grep and awk on the output from ifconfig -a to get the
IPs for use in a shellscript, but the new interface has kyboshed that as
ifconfig puts the interface name and IP address on different lines.

So I thought I should write a short perlscript to produce the
information for the shellscript.

Is there a module I can use to get the information, or will I have to
OPEN an ifconfig pipe and parse what I get from that? I'm trying to
avoid shell calls in perl if I can.

I've searched on CPAN but couldn't find anything that understood both
interface and IP.

Zebee

 

[Zebee Johnstone]

In comp.lang.perl.misc on Tue, 09 Nov 2004 03:51:17 GMT

I've searched on CPAN but couldn't find anything that understood both
interface and IP.

as a followup, I did (afer I posted this of course) find Net::Interface
and Net::Ifconfig:Wrapper, but neither would compile on my system.

This may indicate I'm missing a library, but I've no idea how to find
which one. As far as I know it's pretty complete.

Zebee

 

[A. Sinan Unur]

I have a machine with more than one ethernet interface, and several
IP's aliased to the interfaces.
....

Is there a module I can use to get the information, or will I have to
OPEN an ifconfig pipe and parse what I get from that? I'm trying to
avoid shell calls in perl if I can.

I've searched on CPAN but couldn't find anything that understood both
interface and IP.

http://search.cpan.org/search?query=network+interface&mode=all

returns

http://search.cpan.org/~lds/IO-Interface-0.98/Interface.pm

Does that help?

 

[John W. Krahn]

I have a machine with more than one ethernet interface, and several
IP's aliased to the interfaces.

And several machines with aliases but only one interface.

So I don't want to hardcode interface names like eth0 into anything.

I want a list of IP addresses on the machine and the interface each IP
lives on.

I've been using grep and awk on the output from ifconfig -a to get the
IPs for use in a shellscript, but the new interface has kyboshed that as
ifconfig puts the interface name and IP address on different lines.

If your ifconfig output is the same as mine then this should be close to what
you need:

ifconfig -a | perl -l -00ne'print/^(\w+\s).+?inet addr[\d.]+)/s'


John

 

[Ben Morrow]

Quoth (e-mail address removed):

I want a list of IP addresses on the machine and the interface each IP
lives on.

Try Net:Cap.

Ben