[comp.sources.d] Lyons

geoff@desint.UUCP (04/05/87)

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:
> 
> 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? 

First, a minor but important point:  the author's name is spelled with
a Y, not an I (see the subject line).  This is a common error, because
everybody seems to hear about the book by word-of-mouth.

I have studied Lyons extensively;  I have a copy of Bach although I have
not read it cover-to-cover, but rather have browsed as necessary to answer
certain questions.

The Lyons book is a complete listing (100%, with the exception of some
device drivers) of the V6 kernel.  The listing has been rearranged to
make the presentation more logical, but is otherwise verbatim.  The
entire listing is line-numbered, which is important.  The second volume
consists of a COMPLETE discussion of every single line of code in
the listings, carefully keyed to the line numbers for easy cross-reference.

The Bach book addresses things a bit differently.  To start with, since
the author didn't want to limit his market to source licensees (:-), he
doesn't include a complete kernel source listing.  Instead, he discusses
the major algorithms, and provides sample code (frequently NOT directly
from the kernel, but an equivalent independent implementation).  The
nature of such a presentation tempts the author to diverge somewhat from
the actual implementation (e.g., leaving out uninteresting details and
features), and at least sometimes he does diverge.

If you are relatively unfamiliar with the kernel, or if there are sections
you don't understand (e.g., the interaction of the swapper and scheduler,
which is notoriously tricky), the Lyons book is absolutely unbeatable.  I
got my first look at it after some 6-8 months of working on a V7 kernel,
and it still was tremendously helpful and enlightening (and Unix was not
at all my first encounter with a kernel).

If you have been working on the kernel for several years, I doubt that the
Lyons book will offer much to you.  There will no doubt be a few spots
where it teaches you something, but I think that by and large your reaction
will be "I already knew how bwrite() worked".  This is aggravated by the
age of the book, of course.

The Bach book, on the other hand, is a useful or even necessary reference
work for the modern Unix kernel guru.  It covers both BSD and System V,
and gives a lot of its attention to things that have come along since V6,
such as paging systems, networking, and IPC facilities.  I'd say that its
a must, but like I said I haven't actually read it cover to cover, so I
hesitate to put it that strongly.
-- 

	Geoff Kuenning   geoff@ITcorp.com   {hplabs,ihnp4}!trwrb!desint!geoff

ron@brl-sem.UUCP (04/08/87)

In article <312@desint.UUCP>, geoff@desint.UUCP (Geoff Kuenning) writes:
> First, a minor but important point:  the author's name is spelled with
> a Y, not an I (see the subject line).  This is a common error, because
> everybody seems to hear about the book by word-of-mouth.
> 
> I have studied Lyons extensively;  I have a copy of Bach although I have
> not read it cover-to-cover, but rather have browsed as necessary to answer
> certain questions.

Well, if it is so common a mistake, whoever printed the books made the
same mistake.  Studying both my Bell Laboratories tagged two volume version
and the older single volume (and no mention of Bell) book, both the covers
and the title pages say "LIONS" on them.

-Ron

kre@munnari.UUCP (04/08/87)

The beasts are Johnstone, Hume, Rose, Grevis, Ivanov, Hill, and numerous
others.

Lyons was once an Australian Prime Minister, a little before Lions' time
I think (though its hard to be completely sure :-)  We haven't yet elected
John as Prime Minister, that will take at least one more line by line
commentary (2 isn't enough).

For what its worth, original Lions books had pink & orange covers, if
yours don't, you've gotten substandard duplicates.

They were certainly the ideal way to learn unix, they still are a very
good way, but now you need someone to explain to you just why everything
has changed so much.

kre

andrew@alice.UUCP (04/17/87)

At the risk of being boring, I want to clarify the facts about the Lions text.
As has been stated, the originals were two cheaply bound volumes with
red and orange covers sold by John himself at UNSW. His Unix course
was taught using these books; they were even available for students
during most tests. After the attraction of selling the books wore off
(2 months), John tried to persuade Bell Labs to do it for him. After
some years they agreed although for organisational reasons, it was Western
Electric who acquired the rights from John. The books are readily available
last I knew from the MH Computing [Information??] Library at Bell Labs
at 600 Mountain Ave, Murray Hill, NJ, 07974.

	I like the Lions text better than Bach's because it is exactly the truth.
I learnt Unix using the Lions text and taught Unix as a tutor for Lions.
I may be biased but what does it matter given than Elz has called me an animal?
The point is that Elz is a git from Melbourne who runs BSD4.?. So get
the fluff out of your nose.

mike@turing.unm.edu (Mike Bushnell) (04/23/87)

In article <6808@alice.uUCp> andrew@alice.UUCP writes:
>
>
>...John tried to persuade Bell Labs to do it for him. After
>some years they agreed although for organisational reasons, it was Western
>Electric who acquired the rights from John.

Umm..well..I hate to tell you, but the reason is that Bell Labs was
a subsidiary of Western Electric.  And WE was a subsidiary of AT&T.
Gee..Now WE is called AT&T Technologies, and Bell Labs isn't around.
It is just a faceless bit ot AT&T Tech.
Sigh.

					Michael I. Bushnell
				The one...
				The only...
					B A C H   I I

pdg@ihdev.UUCP (04/23/87)

In article <468@unmvax.UNM.EDU> mike@turing.UUCP (Mike Bushnell) writes:
>Gee..Now WE is called AT&T Technologies, and Bell Labs isn't around.
>It is just a faceless bit ot AT&T Tech.

Yow!  That would certainly bum out the six-thousand-odd people who
work at this Bell Labs site.  Actually, the name just changed from
Bell Telephone Laboratories to AT&T Bell Laboratories.  Certainly not
faceless.  

-- 

Paul Guthrie
ihnp4!ihdev!pdg			This Brain left intentionally blank.

gmd1@ihlpf.ATT.COM (Doughty) (04/27/87)

In article <468@unmvax.UNM.EDU>, mike@turing.unm.edu (Mike Bushnell) writes:
> In article <6808@alice.uUCp> andrew@alice.UUCP writes:
> >
> >
> Gee..Now WE is called AT&T Technologies, and Bell Labs isn't around.
> It is just a faceless bit ot AT&T Tech.
> Sigh.
> 

Not really.

Greg Doughty
AT&T Bell Labs
ihnp4!ihlpf!gmd1