
The DVO locking policy is a little bit broken.  DVO currently
(2009.08.10) requires that users have write access to files because
the code does not distinguish well cases where read-only (soft locks)
are used vs cases of read/write (hard locks) are needed.

DVO uses a somewhat strong locking policy in
order to prevent users from getting inconsistent data.  This is good,
but it prevents DVO letting users have read-only UNIX permissions on a
database: it is necessary to have wrte from being able tb
