I'm interested in getting checkpointing working on NetBSD.  I've
started by looking at userspace checkpointing.  I have code at
http://www.sprc.qut.edu.au/~mcgarry/netbsd/checkpoint.tar.gz
which preserves execution state in an (a.out) executable.  Upon
execution the process recommences execution at the last checkpoint.

Well, it doesn't work.  But the real issue is that when the
checkpoint executable is run as a normal user, the whole machine
locks solid.  The problem occurs when the stack is restored
in recover().

I would appreciate if someone can test the code on NetBSD 1.4.2
and confirm that a normal user can (deterministically) lock a machine.
If this is the case, I will submit a PR.

	-- Gregory McGarry <g.mcgarry@ieee.org>