MULTI_QI  BW0YM4

To optimize network performance, most remote activation functions take an array of MULTI_QI structures rather than just a single IID as input and a single pointer to the requested interface on the object as output, as do local machine activation functions. This allows a set of pointers to interfaces to be returned from the same object in a single round-trip to the server. In network scenarios, requesting multiple interfaces at the time of object construction can save considerable time over using a number of calls to the QueryInterface method for unique interfaces, each of which would require a round-trip to the server.

typedef struct _MULTI_QI { 

        const IID*    pIID;

        IUnknown *    pItf;

        HRESULT       hr;

    } MULTI_QI;

 

Members

pIID

[in] Pointer to an interface identifier.

pItf

[out] Pointer to the interface requested in pIID. Must be set to NULL on entry.

hr

[out] Return value of the QueryInterface call made to satisfy the request for the interface requested in pIID. Common return values are S_OK and E_NOINTERFACE. Must be set to zero on entry.

 

See Also

CoGetInstanceFromFile, CoGetInstanceFromIStorage, CoCreateInstanceEx