#!/usr/bin/perl
use strict;

BEGIN {
    eval {
        require Term::ReadKey;
    };
};
my $use_readkey = 1 unless $@;

print "Enter a secret message", 
    (not $use_readkey ? " (NOTE: message will be visible)" : ''), 
    ": ";
if ($use_readkey) {
    Term::ReadKey::ReadMode 2;
}
my $secret = <STDIN>;
if ($use_readkey) {
    Term::ReadKey::ReadMode 0;
}

print "\nYour message: $secret\n";

print "More typing, to verify normal input echo: ";
my $answer = <STDIN>;
print "You said: $answer\n";