d-l error handling

[jpryzby+d at quoininc.com (Justin Pryzby)]

On Sun, Nov 11, 2007 at 10:19:03AM +0100, Daniel Baumann wrote:
> Justin Pryzby wrote:
> > Comments, please?
> 
> It's great! :) Sorry for beeing a bit slower the last few days..
One thing.  If something fails, it's possible that the virtualfs are
still mounted.  So I suggest that this trap also has some unmount foo:
 for f in proc sys devpts; do lh_chroot_$f remove || continue; done
(continue necessary since this'll be executing in the same set -e
shell as some child helper, and if something isn't mounted the other
things should be umounted anyway).

Justin