Interestingly enough, there's a post just appeared on comp.lang.perl.misc pointing out that $^O is writable (can be modified) - on Windows, at least. I guess if we wanted to dot all of our i's and cross all of our t's we'd have to warn about that, too ... and recommend using $Config::Config{osname} (which actually
readonly) instead.
Heh ... then again, $Config::Config{osname} can always be modified using
....