Before Linux became popular, Minix was widely used for teaching unix internals at universities, due to its available source code (although not under what we would call a Free license these days), clean implementation, and general "smallness" or lack of bloat (and functionality). It made (makes?) wide use of message passing, so students can trace the chain of functions called to perform a particular task.
My first introduction to Unix was by reading that book. -- PerryLorier
Comp301 was a horrible Java concepts class in 2008, but I am led to believe it is back to minix this year (2009). 4/501 is doing a minix related course for 2009 as well, and it rocks! --ShaneHowearth
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