martin@uhccux.UUCP (04/04/87)
In article <3852@amd.UUCP> phil@amd.UUCP (Phil Ngai) writes: >In article <18114@ucbvax.BERKELEY.EDU> schoet@ernie.Berkeley.EDU.UUCP (Steve Schoettler) writes: >> >> Supposing one's site did have source licenses and one had signed >>non-disclosure agreements, how would one get ahold of this book? > >Would someone who has seen both the Lions book and the Bach book care >to comment on whether there is any reason to bother getting the former >now that the latter is available? > I just started reading the group. Are you discussing the two John Lions booklets on the UNIX Level six source code published back in 1977 or so vs. the 1986 Maurice Bach book on the design UNIX OS? If so, the Bach book is both better written and much more complete than the Lions booklets. Basically, the Lions booklets comprise a well-annotated source code listing of an old version of UNIX; the target machine was the PDP 11/40. One booklet was a complete listing of the UNIX source code, including the assembler code for the 11/40. The accompanying booklet explained the source code, defined the variables used, etc. The intention of the booklets was to provide CS students learning about operating systems with an actual case study. They really weren't meant for self-study, as the annotations simply explained how the code worked. You still needed someone to tell you about the various operating system concepts including process control and scheduling, file and memory management strategies, buffers, I/O, etc. On the other hand, the Bach book does a good job of explaining what goes into the design of an operating system, using UNIX as a case study. Finally, sockets, semaphores etc. weren't implemented back in 1977, when the Lions books were written. And 32-bit machines are commonplace now, where the Lions books dealt with a more limited architecture (remember separate I & D space?). In summary, the Bach book is a much better buy, and you needn't go through the legal hassles of non-disclosure in order to own a copy. The Lions book is very out of date, but is an excellent example of how software ought to be documented. But I wouldn't waste the time and energy and money necessary to get a copy. FYI--I no longer have a copy of the Lions books. Brian K. Martin, M.D. ARPA: uhccux!medix!martin@nosc.ARPA UUCP: { ihnp4,ucbvax,dcdwest,seismo!scubed }!sdcsvax!nosc!uhccux!medix!martin
ron@brl-sem.UUCP (04/05/87)
In article <413@uhccux.UUCP>, martin@uhccux.UUCP (Brian Martin) writes: > I just started reading the group. Are you discussing the two John Lions > booklets on the UNIX Level six source code published back in 1977 or so vs. > the 1986 Maurice Bach book on the design UNIX OS? > The Lions books were published as two volumes by Bell Labs. Essentially they split off the actuall source code into a second volume (I guess they considered it more important than the commentary and hence wanted to limit it further). The books have a boiler plate that says they may be copied under the terms of your UNIX license with Western. Version 6 Unix licenses permitted licensees to make copies of the manuals as long as the block about copyright status of the manuals was reproduced (hence one copy that I have is probably legal). The book was also available in a single volume form that bears only the Lions/UNSW copyright. -Ron