-p on LOOKUPs - further clarification?

[Jay R. Ashworth]

On Fri, Jun 15, 2007 at 09:31:19AM -0700, Jeff Harrison wrote:
> --- Dennis Malen <dmalen at malen.com> wrote:
> > Can you clarify the use of the -P, protected lookup. Is the list
> > saying that if you want to write to a lookup file that you use the
> > -P? I was under the impression that you use the -P only if you were
> > pulling information from the lookup file.
>
> The -p should be used ONLY when you do a lookup where you intend to
> do a write. It sounds like you had it backwards - which I believe is
> probably giving you all kinds of grief with unnecessary record locks
> all over the place. Also data corruption could be caused by not using
> the -p when needed.

So, when you say -p, filePro write locks the target record (and
associated index records) *while it is writing that data item* -- and
unlocks it automagically afterwards?

How does that interact with filePro (presumably) caching all write
updates to a record until you save it?

If Ken hasn't already, recently, would you (Ken) mind recapping
*precisley* what set of steps occur that differ when a lookup has a -p
flag, and when a field in that lookup-file is written into?  (Or,
y'know, you can do it, Jeff, if you remember exactly :-)

Cheers,
-- jra
-- 
Jay R. Ashworth                   Baylink                      jra at baylink.com
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