>Would you mind summarizing?
I had this sequence of calls:
if (!::WaitCommEvent(rsThreadData.hPortHandle, &dwEvent,
&rsNotifyOverlapData) )
{
dwError = ::GetLastError();
if (dwError == ERROR_IO_PENDING)
{
bDone = FALSE ;
// Wait for completion of WaitCommEvent().
while (!rsThreadData.bTerminate && !bDone)
{
bDone =
::GetOverlappedResult(rsThreadData.hPortHandle,
&rsNotifyOverlapData,
&dwDummy, FALSE);
dwError = ::GetLastError();
if (!bDone && dwError != ERROR_IO_INCOMPLETE)
bDone = TRUE ; // Real error.
}
}
}
The idea was to make the initial call to wait for a comms event, and then
spin round until the event is completely ready for me to work on (e.g.,
receive incoming bytes).
But it is now this:
if (!::WaitCommEvent(rsThreadData.hPortHandle, &dwEvent,
&rsNotifyOverlapData) )
{
dwError = ::GetLastError();
if (dwError == ERROR_IO_PENDING)
{
// V1.6 Beta 01: Use a wait here, not repeated calls!
// Wait for completion of WaitCommEvent().
::WaitForSingleObject(rsNotifyOverlapData.hEvent, 1000);
bDone = ::GetOverlappedResult(rsThreadData.hPortHandle,
&rsNotifyOverlapData,
&dwDummy,
FALSE);
}
}
Changing from the tight loop to the wait call released a lot of CPU time
back to the system.
--
Jason Teagle
[EMAIL PROTECTED]
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