Odd error

[Jay R. Ashworth]

On Tue, Dec 18, 2007 at 06:59:09AM -0800, Jeff Harrison wrote:
> I have seen this before - I'm not sure where -
> probably this very mailing list.  My understanding of
> a deadlock is that two processes are vying for the the
> same lock or set of locks on the same record at the
> same time.  Usually filepro will just allow the first
> process to create the lock(s), and the second will get
> the "someone updating" message.  For whatever reason,
> it sounds like your process thought that it should be
> able to do it's locks, but so did another process.

A deadlock occurs when process A wants records 1 and 2, and so does
process B, but they lock them in the opposite order from one another.

A simplistic recovery approach is to time out the second lock attempt,
and release the first one, then retry both; this is likely what that
error messae denotes the program having done.

On initial inspection, this is a situation you almost have to *force*
filePro to cause to occur; filePro itself has to be placing both locks
as part of the same operation, in both processes...  I can't intuit
filePro processing code that could cause this.

Cheers,
-- jra
-- 
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