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From: dfbarchan%brock.CDN@ean.ubc.ca (jerry barchanski)
Newsgroups: comp.os.xinu
Subject: xinu vs minix
Message-ID: <85*dfbarchan@brock.cdn>
Date: 25 May 88 16:28:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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I had to select a textbook to a course on design and implementation of operatingsystems last year and I have considered among others books by Comer on XINU
and by Tannenbaum on MINIX. I would need both volumes of the Comer book as an
user interface is described in the second volume only. The first volume containsdescription of communications protocol which did not fit the course on operatingsystems, but they can be skipped without problems. The problem however is the 
hardware for which XINU was designed and the price of the books. The hardware
is LSI-11, rarely used nowadays and another UNIX host computer. There are other
versions ( for Sun, Mac, IBM PC ) but the book describe LSI-11 only so they re-
quire additional text and modified implementation description. The two volumes
of the Comer book are sold in Canada for CDN$ 126 - a prohibitive price for a 
textbook. The new version of the book for IBM PC will be available in January
1989 only - at the earliest - it is not available yet as claimed by prof. Comer.The XINU is very simple in comparison with MINIX and cannot be used as a stand-
alone system - the LSI-11 version has to be downloaded from the UNIX host
to LSI while the Mac version runs under the native MAC operating system and usesits services. XINU does not have its own C compiler so it is necessary to by
additionaly a C compiler - the one for Mac is Aztec for around $400. I wanted
to get the updated version of XINU for the Mac but it looks that I have to pay
for this another $200 as for the original version.
Now about MINIX. It is a 12000 lines , full-blown, message passing operating
system, fully documented in the book, with a C code containing over 3000
separate comments, designed for an IBM PC and compatibles. It costs $79.95.
The hardware for which it is designed is fully described in the book - and it
is the most popular personel computer. MINIX has its own C compiler and the languge
guage is described in the appendix of the book. The book contains an introduction to each aspect of operating systems at first, overview of the mechanisms used
in MINIX and detailed description of the MINIX implementation. Each chapter ends
with exercises with solutions given in a manual for instructors. The book is self
f contained and costs CDN$ 54.85 - a very good price for book of this kind.
So the choice was obvious - I have chosen the Tannenbaum's book and software.