This really filled the void between the amazing hands-on "Lions Book" and Maurice Bach's "The Design of the UNIX Operating System", introducing the reader to some more modern implementation of the UNIX operating system.
There is some bad in the good though, the text varies in quality, not having code anywhere in the book is sometimes a big miss, you can get pretty exhausted reading this, I meant to get this book as bed time reading, it ended up being more of a reference, with only a few chapters being useful, if you're curious about the internals of the actual system get it, but if you need some more theoretical grasp or a "toy problem" book to truly understand the basics, then get Lions book.
Conclusion, I dont regret having it on my shelf, maybe it just could have been better.

Enjoy.

If you are already a BSD kernel expert you might use this as a reference. If you're an advanced "userland" programmer who wants to start learning about kernel internels, this is one way to proceed but, it is very, very difficult.

I wish Kirk had decided to show us more of the joy of programming the kernel. If he had, the book would have been worth at least twice it's current price.

well, just see the authors,..
in my opinion, the overall text is very good designed, easy to read, and gives you a good overview of the kernel.
although im not a professional kernel hacking, it explains you how the system works, lettign you "grep" through the source, (get 4.3 bsd from ftp://ftp.funet.fi/unix first), very good.

While this book has been written by some of the best in the UNIX arena, their strong focus on packing a lot of content into these pages at times can prove a burden to the reader.

Reading through the chapters, it appears that the book could have been rendered more readable if a knowledgeable technical editor had put the finishing touches on it.

Nevertheless, even though it takes a bit of time to get used to the different writing styles and differences in quality of several chapters, this books is a well of insights into the internal workings of BSD 4.4 and its derivatives (like Mac OS X).

In order to gain the most from this title, I strongly urge interested readers to already have worked their way through Maurice J. Bach's "The Design of the UNIX Operating System".

Seriously, despite of the funny little daemon on the cover, this book is quite difficult.

First, it's a technical book about the BSD kernel. The only reason why you would want to read it is that you really want to know How It Works(tm). It's all about kernel. The drivers are only slightly touched, the API is touched even less. Rather than that, this book shows you the fields and flags of internal structures and the ways they are handled. Therefore I'd only recommend it to the system programmers and may be to the enthusiastic admins.

Second, certain chapters are written much worse than the others. The language in chapters 4 (Process Management) and 5 (Memory Management) is sort of a tangled making reading a challenge and it's really a pity because these two topics would better be covered best.

Also note that this book does not include sample code AT ALL. All the principles and algorithms are described using plain English and I'd say it's great, because it's much easier to follow, rather than making your way through somebody else's C scribbling.

Anyway, 5 stars, because it gives you 500 pages of pure distilled info. And it's info from the authors of BSD !

I'm definetely looking forward to read this book again and this is one of the books that are worth it.