Wouldn't something like this be a lot simpler?

So true, but it can be done even simpler!

my (@ips, @names);
while (<DATA>) {
    my ($ip, $name) = split;
    push @ips, $ip;
    push @names, $name;
}
[download]

split with no arguments is like split ' ', $_, which in turn has a special meaning because of the chr(32) string. I think you can asume ip adresses and hostnames do not contain whitespace...

If order and duplicates are not very important, a hash would be really nice:

my %hash  = map split, <DATA>;
my @ips   = keys %hash;
my @names = values %hash;
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