> My favorite formatter was my S100 crate with CP/M, [it's] impossible > to give a single user OS without background processing a virus.
I disagree. I see nothing about "a single-user OS without background processing" that would prevent a virus from infecting other programs, even including the OS, when it's run, and potentially doing something else as well. Perhaps you are using some meaning of "virus" other than "piece of software that infects other software to propagate itself"? That's the only meaning that makes any sense to me. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B