[Ace-users] [ace-users] Associate state/context with asynchronous socket read/write operations

[Douglas C. Schmidt]

Hi Andi,

>I'm new to ACE and I'm trying to use ACE and the proactor pattern for
>some asynchronous data transfers with TCP and UDP. 

Welcome to ACE!  To ensure that we have proper
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$ACE_ROOT/PROBLEM-REPORT-FORM
$TAO_ROOT/PROBLEM-REPORT-FORM

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$TAO_ROOT/BUG-REPORT-FORM

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Naturally, we encourage and appreciate other members of the ACE+TAO
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> My main question at
> the moment is whether there is any way to associate a state or context
> with the asynchronous operation.

Sure - you can use the Asynchronous Completion Token pattern for this.
Please see the discussion of this pattern in the POSA2 book
<www.cs.wustl.edu/~schmidt/POSA/POSA2/> for details.

>When I start the async write or read, I would like to associate some
>state object with that call that I could retrieve again in the
>handle_read_stream or handler_write_stream either from the asynch
>result or from ACE somehow.

Please see Chapter 8 of C++NPv2 <www.cs.wustl.edu/~schmidt/ACE/book2/>
for an overview of the Proactor pattern.

Thanks,

     Doug
-- 
Dr. Douglas C. Schmidt                       Professor and Associate Chair
Electrical Engineering and Computer Science  TEL: (615) 343-8197
Vanderbilt University                        WEB: www.dre.vanderbilt.edu/~schmidt
Nashville, TN 37203                          NET: d.schmidt at vanderbilt.edu