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Subject: Re: Control System Data Access API
From: Ralph Lange <[email protected]>
To: EPICS Core Talk <[email protected]>
Date: Thu, 20 Oct 2005 15:29:09 +0200
Hmm...

You're mixing granularity levels: Nowadays every PV name that doesn't contain a dot is regarded as a record name.

EPICS V4 So, when you're aliasing [particular_device].Setpoint to [particular_record].VAL any generic or display tool will soon start asking for things like [particular_device].Setpoint.EGU .RTYP .DRVH .DRVL .STAT .SEVR and so on and so on.

Do you want to create explicit alias definitions for all (pseudo) fields of that (pseudo) device record? You will end up with zillions of alias definitions on a single IOC.

If you try to escape by aliasing only on the same (record) level, you don't gain as much. Simply having other names for records just creates ambiguity - which of the many names for the same record do you use for archiving? For snapshots? For the alarms? How do you compare snapshots that contain the same record under different names?

Guess this needs more thought - maybe too simple?!

Ralph


Marty Kraimer wrote:
If I read this correctly it is just asking for the CA server to support aliases.

Marty

[email protected] wrote:

Hmmm, a clever and simple idea.

� Ned
Replies:
Re: Control System Data Access API Claude Saunders
References:
Re: Fwd: Control System Data Access API Marty Kraimer
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