Find Which DLL / EXE Created a Window

The GetWindowModuleFileName() functions can be used to find which EXE or DLL has created a window. But the problem with this function is that it will not work across processes.

Whenever we create a window, we have to pass an HINSTANCE into it. Later, we can use GetWindowLong to get that HINSTANCE. Actually the HINSTANCE is nothing but the HMODULE itself. So if we get the hinstance of a window, we can pass this handle to the GetModuleFileNameEx() and simply get the name of the window from other processes as well.

CString MyGetWindowModuleFileName( HANDLE hwindowhandle )
{
    CString csModuleName;
    DWORD dwProcessId;
    GetWindowThreadProcessId( hwindowhandle, &dwProcessId );
    HINSTANCEhModule = (HINSTANCE)GetWindowLong( hwindowhandle, GWL_HINSTANCE );
    if(hModule == NULL)
    {
        return csModuleName;
    }
    HANDLE hProcess = OpenProcess(PROCESS_VM_READPROCESS_QUERY_INFORMATION,
        FALSE, dwProcessId );
    if( hProcess == NULL )
    {
        return csModuleName;
    }
    BOOL bReturn = GetModuleFileNameEx( hProcess, hModule,
        csModuleName.GetBuffer( MAX_PATH), MAX_PATH );
    csModuleName.ReleaseBuffer();
    CloseHandle(hProcess);
    return csModuleName;
}