I have a list of IP addresses that I want sorted in a human readable fashion. A simple sort() on a list of IPs will not work because the octets may be: one, two, or three digits long which confuses sort(). Here is a simple sorting function for a list of IP addresses:

my @ips    = qw(198.15.0.20 4.2.2.1 10.11.1.1 10.100.1.1 65.182.224.40);
my @sorted = sort by_ip_address @ips;

sub by_ip_address {
    return ip2long($a) <=> ip2long($b);
}

Note: You will need my ip2long() function for this to work.