Boulder, Colorado-based XVT Software Inc has introduced Release 3.0 of XVT, its Extensible Virtual Toolkit, which is now also available in the UK from Personal Workstations Ltd of Rotherhithe, South London. XVT Release 3 offers a number of detailed improvements and new features, including support for international character sets, separate menus for each window, and cascading menus. The real value, however, is in a general tidying up of the interface to ensure portability. XVT, which first surfaced back in 1989, is probably the most mature of what is now a growing bunch of tools offering a single developers toolkit for multiple graphical user interfaces – competitors include Neuron Data Inc’s Open Interface and Open Inc’s Aspect. XVT is a set of C libraries for graphical user interface-building that can be linked to your applications at compilation. One set of code – a lot easier to use than the native toolkits, says Personal Workstations – can be used for MS-Windows, Presentation Manager, Open Look, OSF/Motif and Macintosh graphical user interface software, and can also produce a windowing interface for characterbased screens. XVT is not an emulation, it maps directly onto the native toolkit, producing native applications. XVT also rejects the claim that such generic windowing systems have to opt for the lowest common denominator approach in choosing a subset of common functionality between all the windowing systems. XVT includes all the functionality of each system, simply missing out the features not available on a particular system. For instance, it supports the pin-down menu sheets exclusive to the Open Look interface. In the UK, Personal Workstations is now the exclusive distributor of the product. It is interested in adding its own third-party developments to the system, by exploiting existing third-party extensions, such as the XI database interface, XVT++ C++ version and the Decos Windows-alike interface for 80286 personal computers and below. Unlike some competitors, XVT charges no royalty to developers converting its software for sale to their own clients.
