#!/usr/bin/perl open(HANDLE , "result3.txt") || die("Could not open file!"); while() { chomp; use Socket qw( inet_aton inet_ntoa ); sub fr_dotted { unpack 'N', inet_aton @_ ? $_[0] : $_ } sub to_dotted { inet_aton pack 'N', @_ ? $_[0] : $_ } my $next = fr_dotted('100.1.3.41'); my $max = fr_dotted('100.1.3.50'); die if $next > $max; my $new = $next++; $new1 = to_dotted($new); print $new1; } close(HANDLE);