Message from discussion book for system programming confusion

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From: saurabh <saur...@saurabh.org>
Subject: book for system programming confusion
Newsgroups: comp.unix.programmer
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Date: 03 Jul 2009 20:21:29 GMT
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I am a C programmer with more than 3 years experience on Linux platform.
I am looking for a good book that can explain the internals of Unix from
a programmer's point of view.
I searched and inquired , and finally zeroed on following 2 books 

1.Advanced Programming in the UNIX Environment, Second Edition (Addison-
Wesley Professional Computing Series) by Richard Stevens
Link:
http://www.amazon.com/Programming-Environment-Addison-Wesley-Professional-
Computing/dp/0321525949/ref=sr_1_1?ie=UTF8&s=books&qid=1246652000&sr=1-1

2.Advanced Unix Programming
Link:
http://www.amazon.com/Advanced-Programming-Addison-Wesley-Professional-
Computing/dp/0131411543/ref=sr_1_1?ie=UTF8&s=books&qid=1246652342&sr=1-1


I am confused , which one should I buy?
Please guide me on this.
Even if you guys know about some other book which you think is better 
than above 2 ,please do tell me about them

Thanks 
Saurabh