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

Subject: Re: More CA questions
From: Benjamin Franksen <[email protected]>
To: [email protected]
Date: Tue, 16 Mar 2004 00:00:45 +0100
On Sunday 14 March 2004 01:32, Benjamin Franksen wrote:
> ...is it possible to
> circumvent the above mentioned deadlock situation by calling
> ca_create_channel without connection handler and afterwards call
> ca_change_connection_event?

Meanwhile i found out the hard way that this is a bad idea since it opens a 
race window between the two calls, so that initial connection events may be 
lost. This is probably the reason why giving the connection handler in the 
call to create_channel is recommended.

I also found a way to circumvent the deadlock i described (without creating an 
auxilliary task only to handle this situation).

However, i am still interested in answers to my questions. Particularly, a 
more specific explanation of what is meant by "...must wait for successful 
status from ca_pend_io prior to using the channel for the first time" would 
be helpful. In my experiments calling ca_change_connection_event without 
waiting for success from ca_pend_io neither crashes the application nor 
exhibits any other unexpected behavior. So, for the moment i will assume that 
it means the channel may be disconnected and appropriate error codes will be 
returned.

Ben

References:
More CA questions Benjamin Franksen

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