system call to change read/write byte capacity

[redeemed2009]

Hi all,
I'm new to Linux. I compiled and installed the linux kernel version 2.6.27.39. I'm trying to limit the number of bytes that can be read/written for the read/write system calls. I'm trying to write a system call to do this. I found many guides online on how to write a system call, but I have no idea how to proceed with the above.
The functionality should also exist for fork()ed child processes.

Any ideas on where to start would be helpful.
Thanks!

[flakblas]

I have no idea. But, I'm pretty sure this doens't belong in the Linux Newbie section. lol

[redeemed2009]

well where do i post it then?

[Lakshmipathi]

Welcome to LF, redeemed2009 !!!

I'm trying to limit the number of bytes that can be read/written for the read/write system calls.

I don't understand this feature, as far i remember you can pass this as parameter to read/write sys calls. Could you please explain more about your goals.

[redeemed2009]

Hi Lakshmipathi,
I will try to elaborate. I'm trying to implement a system call to set a maximum limit on the number of bytes that can be read or written for the read and write system calls on the caller. forked processes should inherit the limit of their parent.

Does that clear up things a bit? I'm sorry, but I'm also trying to get my head around this as I'm new to Linux myself.

[Lakshmipathi]

In case ,if you trying to set a limit (say read can return max. 512 bytes) anything above (1KB) that will produce an errror message. oops ! sorry - I don't have clue about that.

May be something to do with kernel file tables or process tables...may be wait for some LF member to answer your questions else drop a mail to kernel developer/user mailing list.

[flakblas]

well where do i post it then?

Probably in Linux Programming & Scripting.