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

Subject: CA connection management - vxWorks
From: David Maden <[email protected]>
To: [email protected]
Date: Tue, 22 Jan 2008 09:16:08 +0100
Hi,

I also have a CA connection management problem similar to the recent thread:
         Re: CA connection management problem

but hopefully different enough to warrant a slightly different name.

I'm trying to convert a vxWorks channel access C program from EPICS 3.13.10 to 3.14.8. The program is intended to run once after iocInit and then exit. I get an exception in ca_context_destroy if the channel connection times out.

Reducing the program to its bare essentials, it does the following:

1) Set up ca context with preemptive callbacks enabled:

ca_context_create (ca_enable_preemptive_callback)

2) Call ca_create_channel specifying channel name and callback function.

  3) Wait for callback function to get called:
       If callback function is called, goto step 5.
       If there is a time-out, go to step 4.

4) On time-out, call ca_context_destroy and return with error.

  5) If callback function gets called, continue with calls
     to ca_get, ca_pend_io, ca_context_destroy and return with success.

This runs fine if I specify a PV which is valid.

If I specify an invalid channel name, I get:

    0x15d0250 (tShell): Unhandled C++ exception resulted
                        in call to terminate

The program runs fine under Linux. Is there some problem with ca_context_destroy under vxWorks, which I couldn't find in the Channel Access Reference Manuel or the tech-talk archives? I note, for example, that snl programs under 3.14 are no longer able to exit. Is this related?

Regards, David
--
[email protected]
SLS Project
--


Replies:
RE: CA connection management - vxWorks Jeff Hill
References:
RE: CA connection management problem Owens, PH (Peter)

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