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<== Date ==> <== Thread ==>
Subject: Re: [Fwd: Re: Does DISP work for DB OUT links? Related question]
From: Marty Kraimer <[email protected]>
To: [email protected]
Date: Wed, 03 Sep 2003 09:12:10 -0500
Marty Kraimer wrote:

 > I think EPICS should never write to any record while PACT==1.  (I'd like
 > to say that scanLock should persist through the I/O-wait period of
 > asynchronous
 > processing, so that dbPutField could not modify any field in a lockset
 > while
 > asynchronous processing was going

I can see Tim's desire. Maybe do something like the following:

Extend DISP to have the following meaning:

DISP = (0,1,2) => (puts OK, puts OK unless PACT is TRUE, puts OK always)



Immediately after sending the message I realized that this will not work.

Tim discusses the case where an algorithm is implemented via a set of records some of which are synchronous and some asynchronous. He wants NO CA puts while the algorithm is processing.

This would really be hard to implement in the database. One solution is to use access security. A PV could be used as part of the rules. When the algorithm starts the PV is changed to disable CA puts. When the algorithm completes the PV is changed to allow CA puts.

Marty


References:
[Fwd: Re: Does DISP work for DB OUT links? Related question] Marty Kraimer
Re: [Fwd: Re: Does DISP work for DB OUT links? Related question] Marty Kraimer
Re: [Fwd: Re: Does DISP work for DB OUT links? Related question] Brian Bevins
Re: [Fwd: Re: Does DISP work for DB OUT links? Related question] Marty Kraimer
Re: [Fwd: Re: Does DISP work for DB OUT links? Related question] Marty Kraimer
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