Igor,

<< But why can You leave that to a programmer. If I set session to be
read-only, just assume that no other session will write to the tables and
turn off locking and change detection. >>

That's a support nightmare since there really is no indication of what is
the cause if one of the sessions is actually writing to the tables when it
shouldn't be.

<< Or, here is another idea. Why not put read-only/read-write flag in
dbisam.lck file. On every open check this flag. If it is set to read-only
threat it as read-only attribute. (FMarkedReadOnly) >>

I could, but it would require a major version upgrade so it will have to
wait until that opportunity arrives (if it does).  The problem is that the
..lck file is not versioned, so changes like this cannot be slip-streamed
into place.

--
Tim Young
Elevate Software
www.elevatesoft.com