Kernel documentation and specification

[M. Warner Losh]

In message: <BAY10-F26231E2731D0B73B2E9E00BF400 at phx.gbl>
            "klowd9 -" <klowd92 at hotmail.com> writes:
: First of all i am dead serious about learning.

Good.  You will need to study to learn this topic.  It isn't something
that you can gain in one converstation, or even one day.  It takes
years to completely master things, and even then you'll find subtle
issues to trip you up.

: Secondly, where i come from, $60 is alot of money. And in the spirit of open 
: source and free software, charging $60 for a book is ridiculous.

Then you have to ask yourself if you are willing to earn that $60
another way.  $60 will give you a roadmap.  However, you can also
start in src/sys/kern and study the kernel from scratch.  The source
code is available.  You can ask specific questions here, but it will
take much learning.  You can read the kernel section of the handbook,
and all the man9 man pages that talk about the kernel ABIs.  It will
take you a considerable period of time, with or without the book, to
learn and understand.

However, you can look online for other places that have the book at a
discount.  I paid $35 for mine: It was $50 at a local book seller as a
special, and then I got a 30% off coupon for any one item...  A little
creativeness can solve this problem.  In addition, some libraries also
have copies of this book that they will loan you, which means you'd
get the use of the book for almost free for limited periods of time.

: I want to 
: code free software and contribute to the open source community, must i be 
: prepared to pay inorder to contribute?

No.  I never had to pay to contribute.  You raise a red herring issue
here.  This isn't about pay to play, but rather paying someone a
modest fee to make things easier for you.  You are free to not have to
pay that fee, but it will cost you additional time.

: Why isnt a free copy of this book available online?

Because Kirk has to eat somehow maybe?  Because he spent a lot of time
and effort in the book, but isn't getting rich off the royalties from
it?  All the usual reasons.  It is Kirk's work, he gets to decide how
it is used.

: The author obviously put alot of time and effort into 
: making this excellent book, but so do thousands of other people writing code 
: and papers every day, published freely on the internet, and they ask for 
: nothing in return, besides perhaps, some gratitude

You should study more before making such statements.  I doubt that
anyone could accuse Kirk of being stingy with the code he's
contributed to the FreeBSD project.  He's done snapshots, soft updates
and ufs2, to name just a few things, in the FreeBSD tree.

: Furthermore, you cannot speak with a book, and ask it questions, why some 
: things happen a certain way. A good book will do its best to clerify 
: everything, but it doesnt even come close to what an experienced person can 
: help you understand in half that time.

You can write to hackers@ and hope for the best.  Usually you'll get a
good answer, and usually it will fit your needs.  However, not always.
If you want individualized, guaranteed help, then you'll have to pay
for that service, just like in Linux or any other open source
project.

: And lastly, if i did have some 'real questions', im afraid you wouldnt be 
: able to answer them.

I suggest you study a little more again.  DES likely can answer many
of the questions you might have.  However, being rude to him isn't a
good way to accomplish your goals.  You've come to a forum, hat in
hand, asking for something from us and prepared to give nothing in
return.  At the very least, you need to be polite when you do that, so
that people feel like helping you and taking time out of their busy
schedules to do so.

Warner