Geoff Chappell - Software Analyst
The ITravelEntry methods are (as ordered in the virtual function table after the IUnknown methods):
HRESULT Invoke (IUnknown *);
HRESULT Update (IUnknown *, BOOL);
HRESULT GetPidl (PIDLIST_ABSOLUTE *);
Only one implementation is known, specifically for a class that Microsoft’s published symbol files name as CTravelEntry. This class exists only to support another, CTravelLog, some of whose methods create, manipulate or give access to instances of CTravelEntry. One way to obtain an instance of the CTravelLog class is by calling the GetTravelLog method of an IBrowserService interface. Starting with Windows Vista, instances of CTravelLog are creatable from a CLSID. (For more, see notes on the TravelLog class).
The ITravelEntry interface is implemented in SHDOCVW version 4.71 and higher, until Windows Vista moves the code to IEFRAME and SHELL32.
Though this interface dates from as long ago as 1999, it was still not documented by Microsoft as late as the January 2004 edition of the MSDN Library on CD.
That said, the interface was not completely undocumented. As often for interfaces, the corresponding IID symbol is defined in the UUID.LIB library, even though it is not declared in any header—at least, not any that Microsoft distributes with the SDK.
Moreover, the interface has got documented since, certainly in the SDK dated January 2007 in time for Windows Vista. The interface is there said to be deprecated.