> I guess I would look at the source to copy_to_user() and > copy_from_user() to see how they worked, and figure out how to write my > own copy_from_user_to_user(). copy from user to user directly basically cant be done with 2.2. You cant take page faults for another tasks context that simply. You'd have to do it the way arch/*kernel/ptrace.c does it for the various platforms which is slow and complex. The 2.4 kiovecs can do it in theory. Someone has a demonstration patch doing this for pipes
