> 	cp netbsd /netbsd.new		# ensure more than enough space on root
> 	mv /netbsd /netbsd.old		# keep most recent good kernel around
> 	mv /netbsd.new /netbsd		# nice, atomic operation.
> 
> I don't like using 'cp' to write to /netbsd because programs may have that
> file open, and it's bad to simply overwrite the data out from under them.

Can you explain in a little more detail why this could be a problem?
I have done it both ways, and it seemed to do OK, but, then, I may not
have hit the bad situations, yet.  I would not want to inadvertently
nuke the system because of a poor choice of operations.

What does the overwriting via cp do, vs mv, that would generate bad
situations?

Bob