Question lowlevelkeyboardproc is never called

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C++

Hi,

I have to port a Windows CE application to Windows XP.

In Windows CE this application runs fine. It contains a lowlevelkeyboardproc that is called when a key is pressed.

The different Windows CE projects are build with several makefile-, sources- & *.def- files.

I built new projects with Visual Studio 2010 and added the *.cpp & *.h files.

Further there has been some Windows CE specific stuff in the code, which I replaced with Windows XP stuff.

Concerning the lowlevelkeyboardproc I changed nothing in the existing Windows CE code.

The lowlevelkeyboardproc stuff is implemented in a service (*.exe) and a DLL.
The service loads the DLL. The DLL is the part that contains the hook function.

1. Inside the service a thread is created. Concerning the lowlevelkeyboardproc the following stuff is done in this thread:
---------------------------------------------------------------------------------------------------------------------------

//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
//          MyServiceThread
//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
DWORD WINAPI MyServiceThread (LPVOID lpParameter)
{

   // ... some other code that is executed

    HMODULE hinstDLL = LoadLibrary(TEXT("MyHook.dll"));
    BOOL_FUNC pInstallHook = (BOOL_FUNC)GetProcAddress(hinstDLL,"InstallHook");
   pInstallHook();
 
    MSG msg;
    while(GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    BOOL_FUNC pUnInstallHook = (BOOL_FUNC)GetProcAddress(hinstDLL,"UnInstallHook");
   pUnInstallHook();  

   // ... some other code that is executed

    return 0;
}


2. the lowlevelkeyboardproc related stuff in my MyHook.dll is:
---------------------------------------------------------------------------------------------------------------------------

   ........

//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
//          DllMain
//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
BOOL APIENTRY DllMain( HANDLE hModule,
                       DWORD  fdwReason,
                       LPVOID lpReserved  )
{
   static  HANDLE hFileMap = NULL;

    if( DLL_PROCESS_ATTACH == fdwReason )
    {
        InitializeCriticalSection(&csStatusPos);
      EnterCriticalSection(&csStatusPos);

        hFileMap = CreateFileMapping((HANDLE)-1, (LPSECURITY_ATTRIBUTES) NULL, PAGE_READWRITE, (DWORD) 0, (DWORD) sizeof(SHARED_MEM_VAR), TEXT("MY_SHARED_MEM_VAR") );
      p_my_shared_mem = (PSHARED_MEM_VAR)MapViewOfFile( hFileMap, FILE_MAP_WRITE, (DWORD) 0, (DWORD) 0, (DWORD) sizeof(SHARED_MEM_VAR));

        p_my_shared_mem->m_hDllInst = (HINSTANCE) hModule;
      p_my_shared_mem->m_MyKeyBoardHookObject = new MyKeyBoardHookClass;
      p_my_shared_mem->m_MyKeyBoardHookObject->Init();
      ....

        LeaveCriticalSection(&csStatusPos);
    }

    if(DLL_PROCESS_DETACH == fdwReason)
    {
        EnterCriticalSection(&csStatusPos);
    
      delete p_my_shared_mem->m_MyKeyBoardHookObject;
      .....

        UninstallHook();
      UnmapViewOfFile( (LPCVOID) p_my_shared_mem);
      CloseHandle(hFileMap);

      LeaveCriticalSection(&csStatusPos);
        DeleteCriticalSection(&csStatusPos);
    }

    return TRUE;
}

//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
//          InstallHook
//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
EXTERN BOOL InstallHook()
{
    p_my_shared_mem->m_hMyKeybdHook = SetWindowsHookEx(   WH_KEYBOARD_LL,
                                                                    (HOOKPROC)MyLowLevelKeyboardHook,
                                                                     p_my_shared_mem->m_hDllInst,
                                                                     0 );

    return ! ( NULL == p_my_shared_mem->m_hMyKeybdHook );
}

//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
//          UninstallHook
//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
EXTERN BOOL UninstallHook()
{
   UnhookWindowsHookEx(p_my_shared_mem->m_hMyKeybdHook);

    return FALSE;
}

//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
//          MyLowLevelKeyboardHook
//  xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
EXTERN HOOKPROC MyLowLevelKeyboardHook(int nCode, WPARAM wParam, LPARAM lParam)
{
   ........
}
........

1. Can somebody see, why MyLowLevelKeyboardHook is never called in Windows XP, when a key has been pressed?

2. I tried a lot of stuff to get my Hook installed.... I read a lot in the MSDN about Hooks &
especially lowlevelkeyboardproc etc... I searched in old forum threads for a solution. ...
But I wasn't able to fix the problem. My hook still isn't called.

==> Can somebody tell me please all the important points, that are required to
get a own lowlevelkeyboardproc global hook working.

3. Does somebody know a good link(s) to a place(s), that explains everything about this topic?

4. Does somebody know a good link(s) to a place(s), with a good free sample code?

Thanks in advance for all your answers and help.

regards dave