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<== Date ==> <== Thread ==>
Subject: Re: PyEPICS timeout in jupyter
From: "Shen, Guobao" <[email protected]>
To: Matt Newville <[email protected]>
Cc: Talk EPICS Tech <[email protected]>
Date: Wed, 16 May 2018 20:52:45 +0000

Hi Matt,

I double checked that, and found that when I import pvaccess, the behavior in terminal & in jupyter is same.

 

The pvapy is a Python wrapper of pvaccess (EPICS7 protocol) developed by Sinisa.

It has its own interface for CA client, and does not use libca actually.

But its EPICS7 build does come with a version of libca.

I just happened to find the rare case.

 

Thanks,

Guobao

 

From: <[email protected]> on behalf of Matt Newville <[email protected]>
Date: Wednesday, May 16, 2018 at 12:44 PM
To: "Shen, Guobao" <[email protected]>
Cc: Talk EPICS Tech <[email protected]>
Subject: Re: PyEPICS timeout in jupyter

 

Hi Guobao,

 

On Wed, May 16, 2018 at 12:30 PM, Shen, Guobao <[email protected]> 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

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

Replies:
Re: PyEPICS timeout in jupyter Matt Newville
References:
PyEPICS timeout in jupyter Shen, Guobao
Re: PyEPICS timeout in jupyter Matt Newville
Re: PyEPICS timeout in jupyter Shen, Guobao
Re: PyEPICS timeout in jupyter Matt Newville
Re: PyEPICS timeout in jupyter Shen, Guobao
Re: PyEPICS timeout in jupyter Shen, Guobao
Re: PyEPICS timeout in jupyter Matt Newville
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