#!/usr/bin/perl -w
use strict;

my $all_bits_are_on = -1;
printf ("all_bits => %X\n", $all_bits_are_one);

my $x = $all_bits_are_on + 1;
print "Adding -1 to +1 is: $x\n";

__END__
all_bits => FFFFFFFF
Adding -1 to +1 is: 0