MULTI_QI (Windows Embedded CE 6.0)

1/6/2010

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.

Syntax

typedef struct _MULTI_QI {
  const IID* pIID; 
  IUnknown* pItf; 
  HRESULT hr; 
} MULTI_QI;

Members

• pIID
  Pointer to an interface identifier.

• pItf
  Pointer to the interface requested in pIID. Must be set to NULL on entry.

• hr
  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.

Requirements

Header	objidl.h
Windows Embedded CE	Windows CE 2.0 and later

See Also

Reference

Storage Structures
CoGetInstanceFromFile
CoGetInstanceFromIStorage
CoCreateInstanceEx
IUnknown::QueryInterface