> The software consisted of several routines running concurrently. Both the Data Entry and Keyboard Handler routines shared a single variable, which recorded whether the technician had completed entering commands.

Raise your hand if you've made this type of mistake many times in the past. Most of us have the luxury of not having our software bugs affect human lives.

It's a shame they've removed the hardware safety controls. I don't think I'd even feel comfortable programming such a powerful tool without such circuit breakers.