Unfortunately,

  1. There is no guarantee that the default interface actually connects to the internet (stupid, but not unknown)
  2. Some OSes can have multiple default routes

A much easier method (and avoiding shelling out) is to create an IO::Socket::INET connection and then ask it which IP it binds to:

use IO::Socket::INET;
my $sock = IO::Socket::INET->new('www.google.com:80') 
                             or die "Can't bind : $@\n";
print 'IP Address with gateway to internet: ',$sock->sockhost(),"\n";

[download]

Note that this does not identify which (physical or virtual) NIC has connectivity, but then, neither does the original code, so I am not sure that that was what was actually sought. IO::Interface offers functions to make that connection.

The intelligent reader will judge for himself. Without examining the facts fully and fairly, there is no way of knowing whether vox populi is really vox dei, or merely vox asinorum. — Cyrus H. Gordon

In reply to Re^2: Determining what NIC has an internet gateway by idsfa
in thread Determining what NIC has an internet gateway by slloyd

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