in reply to How many addresses between two IPs?

Cool. I haven't had a look at NetAddr::IP but I had to some similar calculation in one of the NMS programs where we don't want to use non-core modules (in this case to determine if an IP was in a specified network.) In case one is in a similar position of needing to do this calculation and not able to install the module, the code can boil down to:

use Socket; sub add_number_to_ip { my ($ip,$number ) = @_; my $ip_i = ip_to_int($ip); $ip_i += $number; return inet_ntoa(pack('N', $ip_i)); } + sub ip_to_int { my ( $ip ) = @_; my $ip_n = inet_aton($ip); my $ip_i = unpack('N', $ip_n); return $ip_i }
but, yes, you are probably better off using the module if you can.