IXXAT LIN2CAN, Api Manual, Page: 8 / 31

LIN-CAN-RS232 Gateway API (L2CAPI)
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L2C-API Manual, Version 1.6
2.4 Interface IUnknown
The interface provides the following methods:
•
HRESULT QueryInterface([in] REFIID riid, [out] LPVOID *ppvObj)
With QueryInterface, one of the interfaces listed in 2.3 can be
queried. The call is the same as for L2CAPI_CreateInstance, the only
difference being that here no new instance of the class is created, but
a pointer of the required interfaces is returned. By calling
QueryInterface, the reference counter is automatically increased by
one.
•
ULONG AddRef()
AddRef increases the reference counter of the object by one. The
return value is the new status of the reference counter. This method
must be called if an interface pointer itself is cloned.
•
ULONG Release()
With Release, an interface that is no longer required is released
again. The new reference counter status is returned.