It's not really OS dependant, actually. It depends on the terminal / terminal emulator you're using. Term::ReadKey is more low-level, and assumes you will figure out what terminal-type the user has and interpret accordingly.

Perhaps you should look at the source of Term::Readline::Perl to see how it handles multi-char escape sequences, as it uses a similar system as you, with the hashes and all.

bbfu
Black flowers blossum
Fearless on my breath