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Bug in Win32file WaitCommEvent ???

Grant Edwards grante at visi.com
Fri Nov 22 11:40:56 EST 2002 
In article <3dde5012$0$4491$a1866201 at newsreader.visi.com>, Grant Edwards wrote:
>
>> I don't have win32all, but don't you need to have the
>> OVERLAPPED struct persist as well? Isn't the event slot there
>> also used asynchronously?
> 
> Yes, the OVERLAPPED struct has to be persistent.  I've thought
> about using that as storage for the comm event mask value, but
> then we've got to add some sort of accessor function to
> retreive it later.  The advantantage of using a 4-byte buffer
> is that the semantics stay more similar to both the Win32
> usage, and the way that data buffers work for overlapped
> read/write operations:
> 
> 
>    rc,mask = WaitCommEvent(handle,overlapped)
>    rc = WaitForSingleObject(overlapped.hevent)
>    whatHappened = int(mask)

I should have mentioned that in the non-overlapped case, the
returned mask value would be an integer (same as it is now).
That way the only change is to the overlapped usage.

-- 
Grant Edwards                   grante             Yow!  Am I in GRADUATE
                                  at               SCHOOL yet?
                               visi.com
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