| Microsoft DirectX 8.1 (C++) | 
Obtains information about an effect.
HRESULT GetEffectInfo( LPDIEFFECTINFO pdei, REFGUID rguid );
If the method succeeds, the return value is DI_OK.
If the method fails, the return value can be one of the following error values:
| DIERR_DEVICENOTREG | 
| DIERR_INVALIDPARAM | 
| DIERR_NOTINITIALIZED | 
| E_POINTER | 
Note If this method is called on an non-Force Feedback device, E_POINTER will be returned.
  Windows NT/2000/XP: Requires Windows® 2000.
  Windows 98/Me: Requires Windows 98 or later. Available as a redistributable for Windows 98.
  Header: Declared in Dinput.h.