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System Interface IUnknown

IUnknown
 

Usage: you can freely reimplement this interface.


interface IUnknown

Base interface for all CAA interfaces.
Role: All CAA interfaces derive from IUnknown which replaces for UNIX the native Microsoft(R) IUnknown interface. This interface supplies the three basic methods QueryInterface, AddRef and Release to be COM (Microsoft(R) Component Object Model) compliant.


Method Index


o AddRef()
Increments the reference count for the given interface.
o QueryInterface(IID&,void**)
Returns a pointer to a given interface.
o Release()
Decrements the reference count for the given interface.

Methods


o AddRef
public virtual ULONG __stdcall AddRef()= 0
Increments the reference count for the given interface.
Returns:
The reference count value.
This information is meant to be used for diagnostic/testing purposes only, because, in certain situations, the value may be unstable.
o QueryInterface
public virtual HRESULT __stdcall QueryInterface( const IID& iIID,
void** oPPV) = 0
Returns a pointer to a given interface.
Parameters:
iIID
The interface identifier for which a pointer is requested.
oPPV
The address where the returned pointer to the interface is located.
Returns:
S_OK
If the query succeeds
E_NOINTERFACE
If the interface does not exist
Other
If the query fails for any other reason.
o Release
public virtual ULONG __stdcall Release()= 0
Decrements the reference count for the given interface.
Returns:
The reference count value.
This information is meant to be used for diagnostic/testing purposes only, because, in certain situations, the value may be unstable.

This object is included in the file: IUnknown.h

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