Source Code and Commentary on Unix level 6,
by John Lions. The two parts of this book contained (1) the entire source
listing of the Unix Version 6 kernel, and (2) a commentary on the source
discussing the algorithms. These were circulated internally at the
University of New South Wales beginning 1976--77, and were, for years
after, the only detailed kernel documentation
available to anyone outside Bell Labs. Because Western Electric wished to
maintain trade secret status on the kernel, the Lions Book was only
supposed to be distributed to affiliates of source licensees. In spite of
this, it soon spread by samizdat to a good many of
the early Unix hackers.
[1996 update: The Lions book lives again! It was put back in print as
ISBN 1-57398-013-7 from Peer-To-Peer Communications, with forewords by
Dennis Ritchie and Ken Thompson. In a neat bit of reflexivity, the page
before the contents quotes this entry.]
[1998 update: John Lions's death was an occasion of general mourning
in the hacker community.]
