[ug-bosug] Hi.. every one.. want your suggestion..

[Anil Gulecha]

On 8/11/07, KishoreKumar Bairi <prf.kishorekumar at gmail.com> wrote:
> Thanks a lot..
> and its very exciting. to hear that i am going to understand the kernel.
>
>
>
> > (i hope you
> > are familiar with assembly language... if not, its high time that you
> > do so...hehe).
>
> No. I dont know assembly language. So I thought of starting it and googled.
> but  i am really confused now.
> assembly language(ASM) is processor dependent. there are  many  different
> types of  ASMs
> like SPARC instruction set,  ARM instruction set,  80x86  programming,MIPS
> assembly programming etc..etc... I dont even know what all these mean. :(
>
> 1. should i learn all these to learn internals of any kernel??

No. Code in most part of the kernels (both linux and solaris) is
fairly platform independent. You do not have to know assembly language
to understand the code. A good understanding of C is required though.

> 2. since most of kernels are compatible with many processors. Do ther
> developers write instructions in so many ASMs??

Not much. Only the portion that absolutely require using asm stubs
will be written as such. asm is not preferred as it hampers porting.

> 3. Is it not sufficient if i learn only 80x86 programming? should i learn
> all others also.

It depends on your interest. x86 is a fairly popular and widespread
architecture. You can delve into it's details if you are interested in
reverse engineering and such. It definitely helps understand pointers
and working of memory..

> 4. which one should i start with??
>
> > other unix-like OS like {Free,Net,Open}BSD, Darwin.  You can also try
> > FreeDos if you are inclined to experiment with other non-unix os. and
> > probably BeOS (or Haiku). You can get loads of source code if you
> > search on google.
>
> oh.. my god!!!!
> just now downloading the kernel for http://kernel.org its size is 43MB
> (compressed)
> Is it possible to read such a huge size code???
> the code for biggest project i ever did in my life was 1MB (uncompressed)
> Now I am afraid of it a bit. I am sure it takes life time to read 43MB
> (compressed) source.
>

As Zoram mentioned, you have to find your specific area of interest
and follow that portion of the OS.

Anil