I am doing a small project in which i m designing a new system call to encrypt/decrypt files.

My problem goes like this:

1> Previously up until 2.4 , sys_call_table was exported by kernel and so obsolete sys call no. could be used to add our customised syscall.So patching around that obsolete sys call worked.

2> I am designing on 2.6.5 and it doesnt export sys_call_table . So the obvious thing is to modify kernel sources and do development.But this would terribly slow down the work as I have to recompile again and again. I thought using modules is better.

In order to export the sys_call_table in kernel 2.6 i added into the file arch/i386/kernel/i386_ksyms.c the following lines:
extern void* sys_call_table[];
EXPORT_SYMBOL(sys_call_table);

But after recompile , the symbol unresolved problem continues when i run my module.

I googled a lot but couldnt find worthy source. Could u suggest a workaround to add sys call using modules only ?