Hi,

I am developing a function say my_abc() which does the same thing as kernel function abc(). Now I want that instead of using predefined kernel function kernel starts using my function. It might be possible that the kernel function has been used so many places. Anyone having idea how to achieve this.

Thanks.

Hi,
See Implementing a System call in Linux

How are you accessing the kernel function? (e.g. do you want your function to be callable from the shell?)

Perhaps you are trying to write a kernel module?

Or, perhaps you are trying to replace a libc function. What specific function(s) are you trying to replace. It may be a as simple as controlling the order of files provided to the linker.
--- rod.

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Hi,
I feel System Call may not work here.

I want kernel to use my function instead of its own, wherever it is using that function.

I don't know kernel module will work or not ????
If module can do the same then how ?

I am trying to replace swp_entry_t get_swap_page(void).

Please elaborate.

IMO it means compiler judges the function by its header file and executes whatever is written in its definition in the source file.

So if you link your function's header file instead of the default one, then compiler will work according to your function !

Okay, so now that it is more clear that you are actually dealing with a kernel matter, never mind the business about the order of linking; that was only in the case that you were really trying to over-ride a standard library function (distinct from a kernel function).
If you are going to replace functionality that is in the kernel, you will have to write a new kernel driver/module. It may have to be built into the kernel. It will probably be easiest to take the existing module, and modify it to do what you really want it to do.
Kernel programming is a whole different world from userspace programming. There are numerous good articles and even one popular online book that describes kernel level programming. Google is your friend.

--- rod.

Just to say - I like the idea that Ravi has about DOING this in the first place - this sounds immensely cool.
Ravi, when you get it working, please post back in this thread to let us know what worked .