Bug in Win32file WaitCommEvent ???

[Grant Edwards]

In article <areli6$ris$0 at 216.39.172.122>, Bengt Richter wrote:

>==== from an old win32 help file that may have come with an old version of Delphi ?? ======
> 
>   If the overlapped operation cannot be completed immediately, the function returns FALSE and
>   the GetLastError function returns ERROR_IO_PENDING, indicating that the operation is executing
>   in the background. When this happens, the system sets the hEvent member of the OVERLAPPED
>   structure to the not-signaled state before WaitCommEvent returns, and then it sets it to the
>   signaled state when one of the specified events or an error occurs. The calling process can
>                                                                         ^^^^^^^^^^^^^^^^^^^^^^^ 
>   use a wait function to determine the event object's state and then use the GetOverlappedResult
>   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>   function to determine the results of the WaitCommEvent operation. GetOverlappedResult reports
>                                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
>   the success or failure of the operation, and the variable pointed to by the lpfdwEvtMask
>                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>   parameter is set to indicate the event that occurred. 
>   ^^^^^^^^^^^^^^^^
> 
>   If a process attempts to change the device handle's event mask by using the SetCommMask
>   function while an overlapped WaitCommEvent operation is in progress, WaitCommEvent returns
>   immediately. The variable pointed to by the lpfdwEvtMask parameter is set to zero. 
> 
>==========================================
> 
> Sounds like the mask location is safe if you don't call
> GetOverlappedResult??

I sure don't know.  I've found examples that don't call GetOverlappedResult
and they expect a "delayed" write to *lpfdwEvtMask happen.

And I thought it impossible for me to grow to hate Windows even more...

-- 
Grant Edwards                   grante             Yow!  YOW!! Now I
                                  at               understand advanced
                               visi.com            MICROBIOLOGY and th' new
                                                   TAX REFORM laws!!