proc.c:
	as a consequence of the implementation of proc_kill,
	any loop calling sleep should check for p->killed
	and be able to break out with an error return.
	it is better if you check *before* sleep.

	can swap procdump up after proc_kill
	and then have proc_exit and proc_wait on same sheet

	sched ->  switch2scheduler?  or just switch?

	factor out switching and scheduling code from process code

kalloc.c
	more cleanups

ide.c: synchronous disk write -> polling disk write.  search for
       (a)synchronous; xv6 doesn't have asynchronous writes.

fs.c: split all name operations off in name.c?  (starting with namei but move 
      wdir keep in fs.c)

pipe.c:
	more comments?
	comment how functions get called?

sysfile.c:
	is the sys_exec picture upside down?
	can sys_open and sys_exec be simplified any?

general:
	sizeof parens?

L=$HOME/mit/l
(for i in *.c; do xoc -x xgnu -x ./nodecleq.zeta --typesonly $i; done) 2>&1 | grep warning