Minix seems to have a fairly simple compromise. It syncs every time
init sees one of it's children die. This translates to telling a user to make
sure they logout BEFORE rebooting the machine. It's simple, safe, and most 
people can remember this, but it also make sense to people (logging out == 
telling machine I'm done).


                                        Mike Irons

        PS - Is it possible to put update in the kernel?
                It'd be safer there.