Experimental Physics and
Industrial Control System

"Jeff Hill" <[email protected]> · Wed, 4 Dec 2002 16:24:33 -0700

> CA.Client.Exception............................................
> ...
>      Warning: "Virtual circuit disconnect"
>      Context: "134.79.35.35:5064"
>      Source File: ../cac.cpp line 1809
>      Current Time: Wed Dec 04 2002 13:48:18.219267000
> ...............................................................

Do you know for certain that the "read command" is failing or are you
encountering the following situation?

In R3.14 beta 1 and beta 2 the ca client library will print the above
message if a connected channel still exists when you call
ca_task_exit(). To remain strictly backwards compatibility this message
is suppressed, only for this specific situation, in the latest version
of R3.14.

Does ezca block in ca_pend_io() when it is waiting for the "read
command" to complete? If so, then how long is the timeout which is
provided to ca_pend_io()?

Jeff 

> -----Original Message-----
> From: Till Straumann [mailto:[email protected]]
> Sent: Wednesday, December 04, 2002 3:12 PM
> To: Tech-talk
> Subject: libezca and EPICS-3.14
> 
> Hi.
> 
> I discussed this briefly with Marty at JLAB. He suggested
> I should post to the list. I was not sure whether the
> EZCA library is supported under 3.14.
> 
> Here's my problem:
> 
> I have put together a CA interface for SCILAB (a nice open
> source tool a la matlab) who builds on top of libezca. Works
> fine with 3.13.
> Using 3.14_beta1, I can access (e.g. read using ezcaget) a PV
> into SCILAB without problem. An attempt to access the same PV
> a couple of minutes later fails, however, giving the following
> error:
> 
> CA.Client.Exception............................................
> ...
>      Warning: "Virtual circuit disconnect"
>      Context: "134.79.35.35:5064"
>      Source File: ../cac.cpp line 1809
>      Current Time: Wed Dec 04 2002 13:48:18.219267000
> ...............................................................
> .....
> 
> Strange enough, if I repeat the read command for a couple
> of times, it works again. Let some time expire and it again
> fails.
> And so on.
> 
> Does somebody have an explanation or, yet better, a fix?
> 
> -- Till

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System