use strict;
use warnings;

my $opsys = $^O;
print "Hello, your operating system is: $opsys\n";

if ($opsys =~ /linux/) {
    my $nics = qx|/sbin/ifconfig|
        or die("Can't get info from ifconfig: $!\n");

    my @nics = split /(?<=\n)(?=\w)/, $nics;

    for (@nics){
        my ($device) = /^eth(\d)/
            or next;
        my ($ip) = /\bnet addr:([\d.]+)/
            or next;
        print "Device $device has the IP Address of $ip\n";
    }
} else {
    my $nics = qx|ifconfig -a|
        or die("Can't get info from ifconfig: $!\n");

    my @nics = split /(?<=\n)(?=\w)/, $nics;

    for (@nics){
        my ($device) = /^fjgi(\d)/
            or next;
        my ($ip) = /\binet ([\d.]+)/
            or next;
        print "Device $device has the IP Address of $ip\n";
    }
}