Returning HTTRANSPARENT for WM_NCHITTEST in a plugin

How can I get a plugin to make the program have my clicks go though the window? I heard I would have to return HTTRANSPARENT for WM_NCHITTEST. Is it possible to do that with hooking? This is as far as I have got in my hook:

LRESULT CALLB开发者_Python百科ACK myHook(int nCode, WPARAM wParam, LPARAM lParam) 
{
    CWPSTRUCT* pwp = (CWPSTRUCT*)lParam;

    if (nCode >= 0)
    {
    if (pwp->message==WM_NCHITTEST)
        MessageBox(NULL, TEXT("NCHITTEST has been receieved."), TEXT("NCHITTEST"), MB_ICONINFORMATION);                
    }

    return CallNextHookEx(hHook,nCode,wParam,lParam);
}