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<== Date ==> <== Thread ==>

Subject: Record/Channel names
From: Andrew Johnson <anj@aps.anl.gov>
To: EPICS tech-talk <tech-talk@aps.anl.gov>
Date: Mon, 19 Feb 2001 16:28:52 -0600
It is currently possible for a record name to contain any character at all
(quotes have to be escaped with \ but are allowed).  Record names
containing a '.' can't be connected to from other records or via CA, but
there doesn't seem to be any code that prevents their creation.  The IOC
Application Developers guide states that only a reduced subset of ASCII
characters should be used in record names, but this is not enforced in
3.13.  We propose to reinstate the enforcement of this subset.

CA has no restriction on channel names.  Does anybody currently use
parentheses '()' in non-IOC channel names that are provided using the
PCAS?

I'm currently implementing link support (for EPICS 3.15 or 3.16), which
has to provide backwards compatibility with existing databases (i.e. load
existing .db files).  However it appears to be impossible to distinguish
between a new link support address xxx(yyy,zzz...) and an old-style PV
name that contains parentheses.  I therefor propose to provide backwards
compatibility only for databases that don't have links to channel names
containing parentheses.  It will still be possible to connect to such
channels, but the new link support syntax will have to be used for these
connections.

If either of these will cause a problem for your site, please scream now.

- Andrew
-- 
Every great idea appears crazy to start with.


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