#! /bin/bash

trap '' 1 2 3 20
stty -echo
echo -n "Key: "
read key_1
echo
echo -n "Again: "
read key_2
echo
key_3=
if [ "$key_1" = "$key_2" ]
	then
		tput clear
		until [ "$key_3" = "$key_2" ]
		do
			read key_3
		done
	else
		echo "locktty: keys do not match" 1>&2
fi
stty echo