Cookie and XFish

When I blogged about Multics yesterday, I forgot to mention my favorite Multics program. Cookie was a program that you use to use to hack someone’s account when they left a terminal logged in. Once you started it, at random intervals, their terminal would print out messages like:

I want a cookie!

The cute part was that as soon as it printed the message, it would kill off its own process and queue itself up to start again later. This meant that if you did the Multics equivalent of ps (which I’ve since forgotten), you wouldn’t find anything.

The source to cookie is available online.

Several years later, when we started rolling out workstations to people’s desks at Applicon (a mix of Sun 2’s, early Decstations, and custom hardware running X 10), I wrote a program called xfish which was patterned after cookie. It would draw a little fish swimming across your desktop. Once it got to the other side, it would start a copy of the process on another random machine on the network. The first process would exit and the new one would go to sleep for a while. This meant that when you tried to find the process that was drawing the fish, it had probably disappeared from your machine and you had to guess which machine it was sleeping on.

A couple of the new college hires at the time then wrote a shark program which bounced around the network trying to find the fish program and kill it.

I’m afraid that I don’t have source or pictures for either the fish or the shark.