Re: PyEPICS timeout in jupyter

[Matt Newville <newville@cars.uchicago.edu>]

Hi Guobao,

On Wed, May 16, 2018 at 12:30 PM, Shen, Guobao <gshen1@aps.anl.gov> wrote:

Eventually, the root cause was identified.

I have to set the PYEPICS_LIBCA to point to the specific one that pvapy uses.

After that, everything works fine.

Thanks,

Guobao

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From: Shen, Guobao
Sent: Wednesday, May 16, 2018 11:48:12 AM
To: Matt Newville

Cc: Talk EPICS Tech
Subject: Re: PyEPICS timeout in jupyter

 

Hi Matt,

I eventually found my problem.

In my code, I imported pvaccess, which is EPICS7 python client.

Once I commented out that line, the problem disappeared.

OK.  It seems sort of weird that this would only have an impact only with Jupyter, unless the way you started Jupyter used different environmental variables.

I can believe that pvaccess and/or pvapy (are those the same thing?  Sorry, I'm not very familiar with Epics7) would need to point to the same CA shared library.  Well, that assumes pvaccess / pvapy do use the CA library.  From your report, it looks like they must.

With pyepics, we  provide a working, default CA library, but deliberately do not load that at import time so that the default one can be replaced if needed.

--Matt