Memory protection does not protect you from a virus. It can protect other running processes from being modified (if they belong to other users they can't be infected at all; other processes owned by the user it's possible, depending upon the system [1]) but that's it. -spc
Sorry, I was thinking back to the finger file from the ID software guy talking about how horrible MacOS was, not from the perspective of preventing viruses.
I suppose Apple was early in the networking game with Appletalk but not sure if the viruses ever made use of it.
( I grew up Atari -> PC ) -- Ethan O'Toole