system call number

system call number

[mohit verma]

hi all,
suppose a process has invoked some system call and cpu runs the system call
.how can i find out the system call number (invoked) related to that process
in kenrel space?

thanks in advance.
........................
*MOHIT VERMA*
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system call number

[mohit verma]

hi all,
suppose a process has invoked some system call and cpu runs the system call
.how can i find out the system call number (invoked) related to that process
in kenrel space?

thanks in advance.
........................
*MOHIT VERMA*
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system call number

[Mulyadi Santosa]

Hi..

On Sun, Feb 27, 2011 at 20:41, mohit verma <mohit89mlnc@gmail.com> wrote:
> hi all,
> suppose a process has invoked some system call and cpu runs the system call
> .how can i find out the system call number (invoked) related to that process
> in kenrel space?

Untested idea:

check the related process' kernel stack....specificly the first stack
frame. Then cross check it with information from
http://lxr.linux.no/linux+v2.6.37.2/arch/x86/kernel/entry_32.S or your
related arch.

the upper most comment written there will show the meaning of each
values saved in that stack frame. Then what you need to do is just
locate where EAX is...

I think that's one of the ways....probably there are more....


-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com