I used Time::Out for the following example. It'll prompt for a command, but don't enter one. It'll come back with "Operation timed-out". If you enter a command, it'll return "Done".

#!/usr/bin/perl

use strict;
no warnings 'redefine';
use ExtUtils::MakeMaker qw(prompt);
use Time::Out qw(timeout);
use Time::HiRes qw(alarm);

test("Done\n");
if ($@) {
    print "Operation timed-out\n";
}

sub test {
    timeout 20.37, @_ => sub {
        prompt("Please enter command: ");
        print "$_[0]\n";
    };
}
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