Presumably this answers that question once and for all. There's more than one way to do it. Some of the children were very bright, but most of them could have used a lot more adult supervision. P.T. Barnum was correct. Apart from the fact that virusses are supported by their authors, use optimized, small code and usually perform well, none.
Viruses never fail.
Sure it is nice, but there are still too many bugs. Macintosh fans, on the other hand, may note that cockroaches are far more numerous than humans, and that numbers alone do not denote a higher life form. You still get no protection. UNIX is irrelevant. Openness is futile.