On Sat, 2014-11-29 at 18:43 +0530, Jackson Isaac wrote:

I am trying to write hello world system call in linux but I am encountering the following error when I run 'sudo make':

Why "sudo"? That can't be right!

... AR arch/x86/lib/lib.a LINK vmlinux LD vmlinux.o ld: cannot find hello: File format not recognized make: *** [vmlinux] Error 1

I have Linux 3.15.6 in my home directory and have created a hello folder in it. I also made changes to makefile, syscalls.h, and syscall_64.tbl

in make file I replaced

Which Makefile? Don't make us grep the tree, please.

core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/ with core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/ hello

You said hello folder, so I'm _guessing_ you need to add hello/ Note the slash.

Can anyone point out where I am going wrong. I have made the changes first and then I am trying 'sudo make'.

I tried making some minor modifications and running it again 3 4 times but getting the same error and also it takes 2-3 hours of time.

Hope this helps, Paul Bolle