Lions' Commentary on Unix (Paperback)

by John Lions (Author), Peter, H. Salus (Editor)

Editorial Reviews

Product Description
This legendary underground classic, reproduced without modification, is two works in one: the complete source code to an early version (Edition 6) of the UNIX operating system and a brilliant commentary on that code by John Lions. Lions' marriage of source code with commentary was originally used as an operating systems textbook, and remains just as relevant today.

Product Details

• Paperback: 254 pages
• Publisher: Peer-to-Peer Communications Inc.; 6 edition (August 1, 1977)
• Language: English
• ISBN-10: 1573980137
• ISBN-13: 978-1573980135
• Product Dimensions: 10.8 x 8.2 x 0.4 inches
• Shipping Weight: 14.4 ounces (View shipping rates and policies)
• Average Customer Review: 4.9 out of 5 stars See all reviews (9 customer reviews)
• Amazon.com Sales Rank: #459,954 in Books (See Bestsellers in Books)

Customer Reviews

Most Helpful Customer Reviews

94 of 94 people found the following review helpful:

4.0 out of 5 stars The book for Unix kernel geeks, May 28, 1998

By	P. Cooper - See all my reviews (REAL NAME)

The Lions Book was illegally pirated for many years after its publication, with fifth-generation photocopies being the most prized possessions of many Unix kernel hackers.

It was republished shortly after the author died when the politics of the ownership of the Unix sources settled down.

So what's so special about the book?

The first reason is that John Lions believed strongly that just as in literature, where being able to read and analyse great works is more likely to lead to being able to write comparable works, software designers should learn to read and criticise working code. He chose Unix, 6th edition, running on the PDP-11. His book is a subset of the kernel sources, with commentary.

The second reason is that the code itself is, in general, pretty fine stuff. It includes the legendary comment /* you are not expected to understand this */. It's amazing that so much of modern Unix functionality already existed in the mid-70s and ran in only 32kbytes of RAM.

And thirdly, it's a historical document that describes a real operating system, that's come to effect the development of most subsequent system software.

It's a great read, if you're a geek, and you suspect that good code, like good literature should be read and enjoyed.

15 of 15 people found the following review helpful:

5.0 out of 5 stars Elegant and Inspiring, January 31, 2000

By	Dan Milstein (Boston) - See all my reviews

This is the kind of computer book which makes me wish all my friends were programmers so I could share it with everyone I know.

Although the version of Unix it documents is wildly out of date and the C code would make a K&R compiler laugh in disbelief, the underlying elegance of the code shines through. The commentary is brilliant -- Lions pushes the reader to understand for him or herself, all the while providing clear guidance through the most complicated pieces.

Having programmed for years, I've never fully understood such deep mysteries as how process switching works, or how the OS bootstraps itself. Although I am sure that things are much more complex today, having read and pored over this old text and having achieved that elusive feeling of enlightenment, I now feel that it all makes sense.

My only complaint is that they should have printed it as two volumes as it was originally produced. Constantly flipping back and forth was frustrating. But other than that, a total pleasure.

8 of 8 people found the following review helpful:

5.0 out of 5 stars The Way, June 2, 2003

By	Satyadev Nandakumar (Ames, Ia United States/Thrissur, India) - See all my reviews (REAL NAME)

Any comments made on a superlative commentary on superb code would be largely superfluous. This gem should be part of any Operating Systems course. The greatest of the pleasures offered by the book is the opportunity to read the source code, version 6 of the UNIX Operating System. It is a unique opportunity to see the real masters at work!

Highly recommended, with Maurice J Bach's "The Design of the Unix Operating System" as a supplement.