private static int libusb_control_transfer(MonoUsbDeviceHandle deviceHandle, MonoUsbControlSetupHandle controlSetupHandle, int timeout)
        {
            MonoUsbTransfer  transfer        = MonoUsbTransfer.Alloc(0);
            ManualResetEvent completeEvent   = new ManualResetEvent(false);
            GCHandle         gcCompleteEvent = GCHandle.Alloc(completeEvent);

            transfer.FillControl(deviceHandle, controlSetupHandle, controlTransferDelegate, GCHandle.ToIntPtr(gcCompleteEvent), timeout);

            int r = (int)transfer.Submit();

            if (r < 0)
            {
                transfer.Free();
                gcCompleteEvent.Free();
                return(r);
            }

            while (!completeEvent.WaitOne(0, false))
            {
                r = MonoUsbApi.HandleEvents(sessionHandle);
                if (r < 0)
                {
                    if (r == (int)MonoUsbError.ErrorInterrupted)
                    {
                        continue;
                    }
                    transfer.Cancel();
                    while (!completeEvent.WaitOne(0, false))
                    {
                        if (MonoUsbApi.HandleEvents(sessionHandle) < 0)
                        {
                            break;
                        }
                    }
                    transfer.Free();
                    gcCompleteEvent.Free();
                    return(r);
                }
            }

            if (transfer.Status == MonoUsbTansferStatus.TransferCompleted)
            {
                r = transfer.ActualLength;
            }
            else
            {
                r = (int)MonoUsbApi.MonoLibUsbErrorFromTransferStatus(transfer.Status);
            }

            transfer.Free();
            gcCompleteEvent.Free();
            return(r);
        }