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

Subject: Re: write to a single element of an array field
From: Ben Franksen via Core-talk <core-talk at aps.anl.gov>
To: Ralph Lange <ralph.lange at gmx.de>, EPICS Core Talk <core-talk at aps.anl.gov>
Date: Fri, 20 Mar 2020 20:31:38 +0100
Am 20.03.20 um 09:15 schrieb Ralph Lange via Core-talk:
> As filters can change the data type, array size etc., the CA server can't
> just use the information from the record to communicate the data type of
> the channel to the client. Instead, it has to create a fake update (field
> log), push it through the filter chain, and use whatever data type comes
> out at the end.

Indeed I had wondered about the final_* members of dbChannel and what
they might be good for. It would be helpful to have something like this
as a comment in the header file near the place where the members are
defined.

Besides, as their purpose is to be able to answer the question "what is
the element type and number of elements?" /before/ any request is made
(e.g. for CA at connection time), I find the naming of these members as
final_* somewhat misleading, even if that naming is quite natural from
an internal (i.e. operational) POV.

Cheers
Ben

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Attachment: pEpkey.asc
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References:
Re: write to a single element of an array field Ben Franksen via Core-talk
Re: write to a single element of an array field Ben Franksen via Core-talk
Re: write to a single element of an array field Ben Franksen via Core-talk
Re: write to a single element of an array field Ralph Lange via Core-talk
Re: write to a single element of an array field Johnson, Andrew N. via Core-talk
Re: write to a single element of an array field Ralph Lange via Core-talk

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