Xinu

Xinu (`Xinu Is Not Unix`, a recursive acronym) is a Unix-like operating system originally developed by Douglas Comer for instructional purposes at Purdue University in the 1980s. The name is both recursive, and is `Unix` spelled backwards. It has been ported to many hardware platforms, including the DEC PDP-11 and VAX systems, Sun-2 and Sun-3 ...
Found on http://en.wikipedia.org/wiki/Xinu

Xinu

XINU is an abbreviation for XINU Is Not UNIX
Found on http://www.probertencyclopaedia.com/N24.HTM
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