Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Thu, 5 Aug 2010 13:09:21 -0500

On Thursday 05 August 2010 12:43:14 Zhukov, Alexander P. wrote:
> Actually I would go after long plain English names instead of acronyms.
> Of course you are going to use DTL instead of DriftTubeLinac, but you also
> will use DTL in any oral conversation.
>
> I think MPSTripLimit is much better than MTL. Computers obviously don't
> care (as long as you are within maximum length); people do care especially
> if you are talking to someone (over phone at 2AM) and trying to tell PV
> name - long meaningful name is easier than spelling out acronym.

EPICS still has a name length limit, currently 60 characters.  The name is 
stored in a fixed length field in each record, so if you want to make it 
bigger you have to sacrifice the additional number of bytes for every record 
in the IOC, whether they need that or not.

It is also harder to modify PV link fields over Channel Access if the value 
you are writing is longer than 40 characters (in some cases this limits the 
record name to 28 characters), and I believe there is a hard limit of 80 
characters buried in the current code.  These limits are not all that easy to 
remove, we would have done so long ago if they were...

Therefore a preference for verbosity will soon hit limits imposed by the IOC 
software.

- Andrew
-- 
The best FOSS code is written to be read by other humans -- Harald Welte

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System