Re: Knowing if a server application is running

[Andrew Johnson <anj@aps.anl.gov>]

Hi Bo,

On 01/17/2017 09:35 AM, Bo Jakobsen wrote:
> My problem is now that I would like to indicate to the user if the
> Matlab server is running or not through an EPICS record.
> 
> My thought was to periodically (e.g. at least ones per second) update a
> soft record from the Matlab server. But how can I from EPICS test if
> this has happened. It could e.g. be a time stamp, or a "running number".

 From the EPICS perspective your Matlab "server" is a CA client.

The APS uses a recordtype called runcontrol which has an associated
client-side library for controlling client access to subsystems, and as
part of its functionality it has a watchdog to confirm that the CA
client is still running. This may be a bit overkill for what you want,
but it might give you some ideas and you might even be able to reuse the
recordtype.

You can find some information about these in these tech-talk messages:
  http://www.aps.anl.gov/epics/tech-talk/2010/msg00554.php
  http://www.aps.anl.gov/epics/tech-talk/2010/msg00555.php
You'll probably want to start with the manual referenced from the second
message.

HTH,

- Andrew

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