I understand the theoretical implications - but, reading from, http://en.wikipedia.org/wiki/POSIX http://en.wikipedia.org/wiki/POSIX, Windows 2000 was Posix-1 c

I understand the theoretical implications - but, reading from, http://en.wikipedia.org/wiki/POSIX http://en.wikipedia.org/wiki/POSIX, Windows 2000 was Posix-1 compliant, so Posix doesn't really have much in the may of practical implications. What are the practical implications of being "Unix" - i'm of the belief there really are none.