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Subject: Re: Calling ca_context_create(1) too late
From: Tim Mooney <mooney@aps.anl.gov>
To: michael abbott <michael.abbott@diamond.ac.uk>
Cc: tech-talk@aps.anl.gov
Date: Fri, 19 Apr 2013 09:31:22 -0500 (CDT)
Is there any chance you've made any CA calls before calling ca_context_create()?
If so, CA might have made a call to ca_context_create() for you, and may not have
enabled preemptive callbacks, which I understand that you have to enable on an ioc.

saveData calls ca_context_create() after iocInit, so I'm pretty sure that's not
the problem.

Tim
----- Original Message -----
> From: "michael abbott" <michael.abbott@diamond.ac.uk>
> To: tech-talk@aps.anl.gov
> Sent: Friday, April 19, 2013 8:44:09 AM
> Subject: Calling ca_context_create(1) too late
> 
> I've just discovered that calling ca_context_create(1) after
> iocInit() appears to succeed (it returns ECA_NORMAL) ... but the
> resulting context is not very healthy!  In my particular case I find
> that ca_array_get_callback delivers zero length data, but I expect
> other deeper problems are to be found.
> 
> I understand that I need to call ca_context_create() a good deal
> earlier, but I don't really understand why it appears to succeed --
> is it possible for an error code to be returned instead, please?
>  (In some future version of EPICS, I'm testing this on 3.14.11.)
> 
> Alternatively, is there some reliable way I can test whether it has
> succeeded?  I don't have full control over when my library is
> initialised, so detecting an error immediately would be more
> friendly to the user.
> 
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Replies:
RE: Calling ca_context_create(1) too late Mark Rivers
RE: Calling ca_context_create(1) too late michael.abbott
References:
Calling ca_context_create(1) too late michael.abbott

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