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

Subject: ca_get and ca_put triggered by monitors?
From: Dirk Zimoch <dirk.zimoch@psi.ch>
To: EPICS <tech-talk@aps.anl.gov>
Date: Thu, 27 Jun 2013 15:16:04 +0200
Hi all,

I have an application which needs to read or write EPICS data whenever something interesting happens with other EPICS data. The naive way would be to do ca_get and/or ca_put inside a monitor callback function. But as far as I remember, this is forbidden.

Is this (still) true? I cannot find anything about this in the Channel Access Reference Manual.

If it is not (yet) possible, can this be implemented in a future release of the channel access library? I think it is a common use case to "do something when something else happened".

What is the best practice to do monitor triggered channel access at the moment?

One way I can imagine is to setup a different thread blocking on an event semaphore and release that semaphore from within the monitor callback. But this involves thread save programming with all its complications.


Dirk

Replies:
Re: ca_get and ca_put triggered by monitors? J. Lewis Muir
RE: ca_get and ca_put triggered by monitors? Hill, Jeff

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