>Thanks for a very informative answer.
>If Table Buffering is locking the table (like FLOCK()), during TABLEUPDATE, does this mean that I cannot issue a TABLUPDATE if a second person is also using the table in a shared mode?
>Or does TABLEUPDATE try to lock each record to be updated one at a time like RLOCK() while performing the update?

Ah well, when updating you want something like:

If RLOCK()    && you now have the rec to yourself
  {do the necessary updating}
  llSuccess = TABLEUPDATE()
  UNLOCK
Endif

You need to ensure that YOU actually have a lock on a record before attempting the update.

You can be greedy and try to lock with FLOCK() but then no other user can access the table during the batch, and I don't think you want to do that.