Ignoring the interrupt while the terminal is locked

Answer

#!/bin/csh onintr - stty -echo echo -n "Locked. Password: " set guess = $< stty echo echo ""

`onintr -` is the C shell spelling of `trap '' INT`. Without it a Ctrl-C during the read would leave echo off and the terminal unusable — which is exactly the failure the ignore form exists to prevent.

S&K 3e ch15 §15.5-15.6; csh(1)