Hello !

Never before have I been programming using record locking. 
Everywhere I try to find info on it, the docs state that unlocking should
be done on the same region as locking, but nowhere is stated that I can
lock multiple regions.

So: Can I lock multiple regions in one file? And if so, is there a way of
telling how many regions I can lock within a file?

And one more question: _When_ do I use file locking? I suppose it is not
necessary to lock a piece of a file each time I access it, but what is
secure? ie what is the minimum safe situation when you have to lock a file?

The situation I am primarily interested in at the moment:
 I have 2 apps running querying the same database. I know I have to lock a
record when changing its contents, but they run extensive indexing
routines. When I am querying through the index, I do it in a recursively
called routine. So on return of the routine, the index might have changed,
but in the majority of cases it will not. Should I lock the index-block
with shared read access, lock completely, or will this recursively calling
and locking parts of the file exceed the lockbuffers?


Bye, Erik!
[TeamOS/2 NL]
reactions preferrably by echomail
_personal_ reactions preferrably by e-mail
[internet: ErikH{at}hcc-gron.idn.nl]

--- FleetStreet 1.14 NR