Someone else pointed out that you have a recursion loop.

Reading the code, I think you would benefit from given/when instead of a cascade of elsif statements.

But... maybe you should make a hash as a keyboard mapping. This will not only make your loop simple as all the logic is elsewhere, but allow you to remap the keyboard.

my $key = ReadKey(-1);
next unless defined $key;  #next or return depending on your code stru
+cture
if ($key eq "\e") { #expecting more
   $key .= ReadKey(-1);  # should be a '['
   $key .= ReadKey(-1);
   }
my $callback= $keymap{$key};
if (defined $callback) {
   $callback->($key);
   }
else { beep(); }  #no such key is meaningful here
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That is, the gathering is centralized, and separate from the code dispatched to. The $key is passed as an argument in case you have common subs for several keys and need to distinguish between them.

—John