Another troubling thought is that I thought OS X was built on top of BSD, a very mature and secure OS. How did this get past the BSD layer?
It's believed the problem lies in the way OSX deals with the guest account. OSX is set up to automatically delete any files found in the guest account's home directory once the guest logs out.
That's not a bad idea actually.
Purging the guest directory eliminates the risk of having something left behind that can screw up the system. It also guarantees each person who subsequently logs in as a guest gets their own "clean set of sheets" so they're not put at risk either. Minimizing risk is the entire point of a having a guest account to begin with.
From what I understand, apparently something happens in OSX if you logout of a regular account and then log into the guest account. Because if you logout as guest after that - and then immediately log back into your regular account
- that's when the glitch occurs.
Somehow, the files in the regular login's home directory get purged along with the guest's. That's an Apple original if there ever was one.
That gremlin has nothing to do with BSD since the same thing doesn't happen in BSD. Or Linux. Or Windows. Or...