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	TN038: MFC/OLE IUnknown Implementation (Visual C++ 6.0) (Site not responding. Last check: 2007-10-23)
		Although the IUnknown interface is referred to as a C++ class, COM is not specific to any one language — it can be implemented in C, PASCAL, or any other language which can support the binary layout of a COM object.
		OLE refers to all classes derived from IUnknown as "interfaces." This is an important distinction, since an "interface" such as IUnknown carries with it no implementation.
		This is made easier with a standard implementation of IUnknown as well as a number of macros that eliminate some of the repetitive code.
	msdn.microsoft.com /library/en-us/vcmfc98/html/_mfcnotes_tn038.asp?... (3596 words)

	Using COM Objects from Java - Microsoft Technologies for Java
		When all the clients using the COM object have released their references, the COM object removes itself from memory, and then unloads the associated library or application if it was the last object being used from that COM object provider.
		IUnknown is the base interface in COM that every COM object must implement.
		All COM interfaces extend IUnknown, have vtables that contain the three IUnknown methods in exactly the same vtable positions, and append their own methods to the base IUnknown vtable.
	research.microsoft.com /~chadv/java_com2.htm (6082 words)

	OLE Component Object Model (Site not responding. Last check: 2007-10-23)
		As part of the IUnknown interface, OLE defines a standard function, called QueryInterface, through which the user of one interface of an object can obtain a pointer to another interface of the same object.
		The implementation of the IUnknown functions in each supported interface must be "aware" of the entire object, because they must be able to access all other interfaces in the object and must be able to affect the object's reference count.
		Through the IUnknown interface, a user can obtain pointers to other interfaces that the object also supports, but this means obtaining a different pointer that refers (indirectly) to the same object.
	www.objs.com /x3h7/ole2.htm (4073 words)

	Irrlicht Engine: irr::IUnknown Class Reference
		Most objects of the Irrlicht Engine are derived from IUnknown, and so they are reference counted.
		When you create an object in the Irrlicht engine, calling a method which starts with 'create', an object is created, and you get a pointer to the new object.
		The IUnknown class provides a basic reference counting mechanism with its methods grab() and drop().
	irrlicht.sourceforge.net /docu/classirr_1_1_i_unknown.html (751 words)

	PRB: Visual Basic and Visual Basic for Applications Do Not Understand IUnknown** Data Type in MIDL Type Library
		However, a similarly written Visual Basic component that uses the hidden IUnknown data type (which equates to an IUnknown** in C/C++) displays correctly in the Object Browser and can be called by another Visual Basic class or used by Visual Basic Implements without error.
		MIDL-generated type libraries represent an IUnknown** parameter as a VT_UNKNOWN in the TYPEDESC for the ELEMDESC struct that describes the parameter.
		Because programmers are not allowed to use an IUnknown** data type natively in Visual Basic and VBA, components that are designed to work in these programming environments should avoid using this type when possible.
	support.microsoft.com /support/kb/articles/Q194/9/13.ASP (1384 words)

	VB Binding Tutorial
		Many developers incorrectly refer to the interface as all the exposed properties, methods and events of the class, although these things are part of the interface, they are not the interface it self.
		All COM objects must expose the Interface IUnknown, IUnknown is the base interface for all COM interfaces exposed, and reside behind IUnknown in the interface hierarchy.
		IUnknown manages the lifespan of the COM object and handles client requests for interface access.
	kandkconsulting.tripod.com /VB/Tutorials/vb_binding_tutorial.htm (1036 words)

	Microsoft ActiveX SDK
		Aggregation is almost as simple to implement as containment is, except for the three IUnknown functions: QueryInterface, AddRef, and Release.
		The catch is that from the client’s perspective, any IUnknown function on the outer object must affect the outer object.
		The solution is that aggregation requires an explicit implementation of IUnknown on the inner object and delegation of the IUnknown methods of any other interface to the outer object’s IUnknown methods.
	www.maya.com /local/doc/activex/html_format/com_13.htm (502 words)

	A Pointer To IUnknown? - GameDev.Net Discussion Forums
		Posted - 9/24/2003 9:58:01 AM and because every COM-interface should derive from IUnknown, you should be able to do a cast (which would even be dangerous).
		If you are using a COM object you will always have IUnknown.
		I can only be sure about one thing: it's that IUnknown is present on the computer.
	www.gamedev.net /community/forums/viewreply.asp?ID=1113522 (875 words)

	Introduction to COM (Site not responding. Last check: 2007-10-23)
		IUnknown was declared by Microsoft, and is part of the COM run-time libraries.
		Because all interfaces descend from IUnknown, an implementation of the 3 IUnknown methods must exist in order to use the IEmployee interface.
		TInterfacedObject takes care of the details of implementing IUnknown, so you are free to concentrate on implementing the interfaces you declared.
	www.distribucon.com /papers/comintro/2112.htm (4942 words)

	The Active Template Library Makes Building Compact COM Objects a Joy
		ATL is representative of the movement away from monolithic, single-tier applications and serves as a good substrate for developing the lightweight COM components required for modern distributed applications.
		This pattern is so ingrained in every COM programmer's soul that they often do not write the statements that actually use the pointer until after typing the Release statement at the end of the block.
		Second (and most important), it is illegal to use CComQIPtr with IUnknown because of the overloaded constructor and assignment operator.
	www.microsoft.com /msj/0697/atl.aspx (7709 words)

	Iunknown Training - Learn iunknowns study Iunknowning training classes Iunknown courses (Site not responding. Last check: 2007-10-23)
		This course investigates advanced concepts and technologies that will help you develop more capable and reliable client/server applications with Visual Basic.
		It discusses the attributes of interfaces and the concept of an interface as a contract.
		It examines the basic IUnknown interface the creation and implementation of abstract classes and multiple interfaces and the fundamentals of the Interface Definition Language (IDL).
	www.training-classes.com /course_hierarchy/keyword_index/iunknown.html (159 words)

	Reference counting - Wikipedia, the free encyclopedia
		Microsoft's Component Object Model (COM) makes pervasive use of reference counting.
		In fact, two of the three methods that all COM objects must provide (in the IUnknown interface) increment and decrement the reference count.
		Since much of the Microsoft Windows graphical user interface and many Windows applications (including MS Internet Explorer, MS Office, and countless third-party products) are built on COM, reference counting has arguably been a wildly successful memory management strategy.
	en.wikipedia.org /wiki/Reference_counting (2262 words)

	VSJ \| Articles \| Into the IUnknown
		You then pass the IUnknown QueryInterface the Iid of the Interface you really want to use and it passes back a pointer to it.
		An IDispatch Interface is a special type of IUnknown Interface that includes methods that allow methods to be called by name at runtime.
		Notice that the ComInterfaceType doesn’t mean that this is an IUnknown interface but that it should be treated by the Framework as if it was derived from IUnknown.
	www.vsj.co.uk /articles/display.asp?id=558 (4350 words)

	IUnknown (Site not responding. Last check: 2007-10-23)
		The IUnknown interface is a common interface supported by all OLE objects and, therefore, by all speech objects.
		An application uses IUnknown to obtain pointers to other interfaces supported by an object and to manage the interface pointers after obtaining them.
		Increments a reference count for every new copy of an interface pointer to a specified interface on a particular object.
	www.text-reader.com /ttshelp/iunknown.html (262 words)

	kbAlertz: (233359) - The following error is generated when trying to build a Java project that imports a COM component ... (Site not responding. Last check: 2007-10-23)
		The problem is that JActiveX generates Java code that treats IUnknown as a user-defined type, rather than as com.ms.com.IUnknown.
		This DLL implements a property declared to be of type IUnknown.
		The problem is that Visual Basic is marking the IUnknown property type as a user-defined type (VT_USERDEFINED) instead of the usual IUnknown (VT_UNKNOWN).
	www.kbalertz.com /kb_233359.aspx (635 words)

	Interface inheritance
		The OP has multiple IUnknown objects, so if those objects had some state then it could make a difference.
		Actually it can derive from other interfaces, and I think this is why those casts are needed, this is multiple inheritance with some of the base classes being the same (like IUnknown).
		Yes, but base classes (interfaces) of powerful_engine_object class all derive from IUnknown.
	www.codecomments.com /message313245.html (850 words)

	[No title]
		Despite the fact that Delphi gives us these IUnknown niceties, it is still possible to bypass the compiler code and incorrectly use IUnknown.
		Since TEchoCallback's IUnknown implementation is useful for interface implementers, Delphi encapsulates this logic into the TInterfacedObject class.
		Another type of interface that may be implemented by a Delphi client is a dual interface.
	www.techvanguards.com /stepbystep/comdelphi/insideclient.asp (3014 words)

	The Old New Thing : The ways people mess up IUnknown::QueryInterface
		IShellFolder psf; IUnknown* punk; CoCreateInstance(CLSID_xyz,..., IID_IShellFolder, (void)andpsf); psf->QueryInterface(IID_IUnknown, (void)andpunk); CoCreateInstance(CLSID_xyz,..., IID_IUnknown, (void)andpunk); punk->QueryInterface(IID_IShellFolder, (void*)andpsf);
		Yet this is perfectly legal since all objects derive from IUnknown.
		Besides, it would prevent querying for interfaces other than IUnknown, so I don't really think that would be more correct.
	blogs.msdn.com /oldnewthing/archive/2004/03/26/96777.aspx (3048 words)

	IUnknown
		The IUnknown interface provides methods to obtain and manage pointers to interface objects.
		Every COM object must support the IUnknown interface and all interfaces are derived from it.
		A globally unique identifier for interface type checking and casting.
	research.microsoft.com /invisible/IUnknown.htm (1477 words)

	FIX: Visual C++ 5.0 #import Causes Errors with ADO Version 2.0
		On a clean Windows 95 or Windows 98 machine with DCOM95 or DCOM98 installed, compile the following in a.cpp file:
		error C2664: '_com_issue_errorex' : cannot convert parameter 2 from 'struct ADODB::_Connection const ' to 'struct IUnknown* *'
		NOTE: This problem also occurs on Windows NT 4.0, and the resolution given applies.
	support.microsoft.com /support/kb/articles/Q190/7/26.ASP?LN=EN-US&... (481 words)

	DirectX Interfaces
		For a description of methods and parameters, see d3d.
		For a description of methods and parameters, see d3dDevice.
		For a description of methods and parameters, see d3dLight.
	www.hi.is /~snorri/SDK-docs/x/exten145.htm (1213 words)

	microsoft.public.vc.atl: Re: How to get IUnknown pointer?
		In reply to: Simon Trew: "Re: How to get IUnknown pointer?"
		Next in thread: Simon Trew: "Re: How to get IUnknown pointer?"
		Reply: Alexander Nickolov: "Re: How to get IUnknown pointer?"
	tech-archive.net /Archive/VC/microsoft.public.vc.atl/2004-03/0307.html (238 words)

	HaskellDirect User's Manual - version 0.26: Support libraries: The ComServ library
		Given the state of the component instance and its method table, this action does the bare minimum of creating an interface pointer.
		The file path to the Win32 DLL containing the component.
		To use this component from Haskell, let's assume that we've used HaskellDirect to generate a client stub for
	www.haskell.org /hdirect/user-34.html (1503 words)

	Exploring MFC - Understanding ATL
		My life is easier because I no longer have to code IUnknown by hand.
		The derived class should implement this function to return a pointer to an array of structures, defining each of the interfaces the class supports.
		CoCalc* pCoCalc = new CoCalc; IUnknown* pUnk; pCoCalc->QueryInterface(IID_IUnknown, (void**)&pUnk); // pUnk->Release();
	pluralsight.com /articlecontent/cpprep0398.htm (2068 words)

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