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<== Date ==> <== Thread ==>

Subject: Re: Record processing knowledge of dbAccess context
From: Peregrine McGehee <[email protected]>
To: Marty Kraimer <[email protected]>
Cc: "Peregrine M. McGehee" <[email protected]>, <[email protected]>, <[email protected]>
Date: Fri, 9 Apr 2004 08:18:23 -0600 (MDT)
To set the historical record straight, on 14 February 2003
David H. Thompson (ORNL) posted -

> I also noticed in the record reference manual that the PUTF field is a
> logical that happens to be set if dbpf, or channel access, is writing a
> value to the record and if SCAN is passive.  This lets the device
support
> know that data should be written instead of read.  Scanning can be
> accomplished by using an flink from something that is scanning, say a
> fanoutRecord.

As you pointed out, the use of PUTF does not afford a
general solution and that this is only valid for a specific
combination of record linkages and CA client actions:

1. the record must be scan Passive.
2. the "write" action must be triggered by a dbPut to a field
with Process Passive set.
3. the "read" action must be triggered by a FLNK.

Is the latter condition equivalent to someone calling dbProcess()
directly?


On Fri, 9 Apr 2004, Marty Kraimer wrote:
>
> It is also a little scarry because it means that the original feature
> must not be changed in such a way that it breaks the new usage.

- Peregrine
-- 
Peregrine M. McGehee	Department of Astronomy
New Mexico State University, Las Cruces, New Mexico


Replies:
Re: Record processing knowledge of dbAccess context Peregrine McGehee
Re: Record processing knowledge of dbAccess context Marty Kraimer
References:
Re: Record processing knowledge of dbAccess context Marty Kraimer

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