Experimental Physics and
Industrial Control System

Benjamin Franksen <[email protected]> · Tue, 12 Apr 2005 19:49:18 +0200

On Monday 11 April 2005 16:56, Liyu, Andrei wrote:
> 	If I am not mistaken there are not couple features in current CA
> function interface.
> 	I can suppose that when you came to multithread CA you added
> get_current_context and attach functions. But there is not similar
> mechanism for ca_context_destoy.
> 	So I open first thread, create CA context, create first CA
> channel. Then I open second thread, attach to current CA context, create
> second CA channel.  ... Then I decide to close first CA channel and
> close context (???!!!). What is behavior CA library? I suppose second CA
> channel will be closed without normal procedure of closing second
> channel + its monitor?
> 	But I don't like to close second channel and CA context! Then I
> should check is that channel latest? I couldn't find suitable function
> in CA function API. Maybe get_current_context has something. But it is
> very deep.
> 	I have once way - hold tracks of my CA channels (minimum is
> global counter). Usually it could be done. But if program is mixture of
> different libraries and each library comes to CA library then it becomes
> impossible.

Hi Andrei,

I asked Jeff a similar thing a while ago. Specifically, I asked for a feature 
ca_detach_context that would be the opposite of ca_attach_context (and could 
also be used to detach the thread that created the context in the first 
place[*]). He seemed to be open to the suggestion but I don't know if it is 
planned to be included in the next epics release.

Ben

[*] ca_create_context in fact does two separate things: It creates a context 
and then attaches the calling thread to it; whereas ca_destroy_context first 
detaches context from the caling thread, then destroyes the context.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System