Question

I have wince 6.0 applcaion in which inside thread applcation is waiting for event which driver will set. i have created event inside applcation and samevent in driver also. butwhen driver set the event then appcation is not able to catch it.(driver is setting event successfully)

Here is code

// application side
m_hEvent = CreateEvent(NULL,FALSE,FALSE,L"MY_EVENT");
if(m_hEvent)
{
    if(!DeviceIoControl(m_hDriver,CREATE_MY_EVENT,
        (LPDWORD)&m_hEvent,NULL,NULL,NULL,NULL,NULL))
    {
        AfxMessageBox(L"not created event successfully in driver");
    }
    while(TRUE)
    {
        //waiting for driver to setevent
        int RetValue = WaitForSingleObject(m_hEvent,INFINITE);
        if(0 == RetValue )
        {
            AfxMessageBox(L"wait end");
        }
        else
        {
            AfxMessageBox(L"time out");
        }
    }
}

…

//Driver side
BOOL SMP_IOControl(DWORD hOpenContext, DWORD dwCode, 
                   LPDWORD pBufIn, DWORD dwLenIn, LPDWORD pBufOut, 
                   DWORD dwLenOut, PDWORD pdwActualOut)
{
    switch (dwCode)
    {
         case CREATE_MY_EVENT :
         {
             m_hEvent = (HANDLE)(*pBufIn);
             if(NULL != m_hEvent)
             {
                 // getting this message
                 MessageBox(NULL,L"event successfully created",L"success",MB_OK); 
             }
             else
             {
                 MessageBox(NULL,L"no event successfully created",L"success",MB_OK);
             }
         }
         break;
         case SET_EVENT:
         {
             //set event that which application waiting
             if(SetEvent(m_hEvent))
             {
                 // getting this message
                 MessageBox(NULL,L"event set successfully",L"success",MB_OK); 
             }
             else
             {
                 MessageBox(NULL,L"event set successfully",L"success",MB_OK);
             }
         }
         break;
     }
}

Answer 1

The inherent problem here is that you’re having one process (your app) create a HANDLE and then passing that HANDLE to the another process (device.exe) and expecting it to be valid. It’s not.

In this case the solution is simple. System events are unique across the OS by name, so simply call CreateEvent in both places using the same text name. When you call SetEvent in one process, the other process waiting on the HANDLE it created will get signalled.

That means remove your CREATE_MY_EVENT IOCTL (and that’s a non-standard naming convention, BTW, it should start with “IOCTL_”) handling in the driver and just call CreateEvent in the SMP_Init method and store that HANDLE.