Experimental Physics and
Industrial Control System

Florian Feldbauer via Tech-talk <[email protected]> · Tue, 18 Jun 2019 16:04:08 +0200

Thanks for this explanation!!

Yeah, you are right. Which Python I'm using would have been the better

information.

I installed python via 'apt install python3 python3-pip' so for Debian

Stretch it's currently python 3.5.3!

I have now started to use p4p in my small project and it works quite

well! And so far the documentation is also very useful!

Cheers,
Florian

On 6/18/19 3:46 PM, Michael Davidsaver wrote:

On 6/17/19 10:05 AM, Florian Feldbauer wrote:

Hey Kay and David,

during the EPICS7 training at the collaboration meeting, we were using a PVA client written in python.
This client imports the module "pvaccess".

For a small project I wanted to write my own PVA client in python, but I cannot find this library.
Using `pip search pvaccess` I found a module called p4p (maintained by David?) instead.
Googeling I found also pvapy which I could not install via pip.

P4P is my own python binding for PVA.  I have been, and will continue,
to support and recommend it.  It one of the tools I use when developing and
testing PVA itself, and gets a fair amount of exercise for this alone.

Are there any recommendations which module to use?

1. I provide instructive as well as reference documentation https://mdavidsaver.github.io/p4p/

2. P4P tries to conform to python conventions (eg. use of logging, unittests, exception handling, ...)

3. P4P support three concurrency primitives: OS threads, asyncio (py >=3.4 only), and DLS cothreads.

4. I support building P4P as an EPICS module (cf. configure/RELEASE) and as a python package (cf. setup.py)

5. I publish both binary and source to pypi.org.

https://pypi.org/project/p4p/#files

Binaries are currently provided for Linux, Mac, and Windows for python 2.7, 3.4, 3.5, and 3.6.

As a source build is provided, it will be used when no pre-built binaries match (just takes longer).

6. When built as a python package, P4P uses the 'epicscorelibs' python package.  This is
    EPICS Base built from source with a setup.py!

In case it matters: My environment is Debian Stretch with Base 7.0.2.2.

More relevant is while python version, and how you install it (eg. debian package vs. conda vs. ???).

--
Dr. Florian Feldbauer

Ruhr-Universität Bochum
Experimentalphysik I AG
Universitätsstr. 150
Fach-Nr. 125
D-44801 Bochum

Office: NB 2/134
Phone:  (+49)234 / 32-23563
Fax:    (+49)234 / 32-14170
https://paluma.ruhr-uni-bochum.de

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System