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I am writting an application which talks ( reads and rwrites ) from a serial port. I am using overlapped file I/o

I am writting an application which talks ( reads and rwrites ) from a serial port. I am using overlapped file I/o asynchronously. I keep getting an invalid handle message from my WaitForMultipleObjects code and cannot figure out why. Here is the offending code:

DWORD result = ::WaitForMultipleObjects(2, waiters, FALSE, INFINITE);
switch(result)
{ /* wait */
case WAIT_OBJECT_0: // shutdown
                              {
::CancelIo(parms->hCom);
shutdown = ERROR_SUCCESS; // clean shutdown
running = FALSE;
continue;
                              }
case WAIT_OBJECT_0 + 1: // I/O complete
                              {
ok = ::GetOverlappedResult(parms->hCom, &ovl, &bytesRead, TRUE);
if(!ok)
{ /* GetOverlappedResult failed */
DWORD err = ::GetLastError();
running = FALSE;
continue;
} /* GetOverlappedResult failed */
break;
                              }
default:
{ /* trouble */
shutdown = ::GetLastError();

/////// This GetLastError returns 6, which means invalid handle. Is it the CEvent handle, or my serial port handle?

I am stumped.

Thanks
ASSERT(FALSE); // failure
running = FALSE;
continue;
} /* trouble */
} /* wait */

jkr

How is 'waiters' declared and how are you filling it?

JoeBarryTwinstar

ASKER

It has 2 handles

I is 0x0000 and is named shutdown
the other looks like a valid handle and came from CreateEvent in an overlapped i/o structure

jkr

Err, what about some more - details. How is 'waiters' in

DWORD result = ::WaitForMultipleObjects(2, waiters, FALSE, INFINITE);

declared and how are you filling it?

ASKER CERTIFIED SOLUTION

DanRollins

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