IUnknown::QueryInterface

HRESULT IUnknown::QueryInterface (REFIID riid, LPVOID FAR *ppvObj);

Retrieves the address of a specified interface on a particular object so that an application can query an object to determine what interfaces it supports.

· Returns NOERROR if successful, or one of these error values:

CO_E_OBJNOTCONNECTED
E_NOINTERFACE
E_OUTOFMEMORY
E_INVALIDARG
E_UNEXPECTED
REGDB_E_IIDNOTREG

riid

[in] Interface identifier of the interface to be retrieved.

ppvObj

[out] Address of a variable that receives the address of the specified interface on the object. If the interface specified in riid is not supported by the object, the function returns E_NOINTERFACE. All errors set *ppvObj to NULL.