Kenton Lee

1996 X Technical Conference Preview

by Kenton Lee

January, 1996

Copyright © 1996 Kenton Lee, All Rights Reserved.

The oldest and most technically oriented conference covering the X Window System is the X Consortium's Technical Conference. After years of freezing winters in Massachusetts, the X Consortium finally decided that they'd get a better turn out by holding the conference in warm Silicon Valley. The tenth annual edition of this conference will be held February 12-14, 1996 in San Jose, California. The schedule and registration information are available on the World Wide Web at You may register by mail or on site.

If you found the material in my The X Advisor columns to be interesting, I'm sure that you'll enjoy the conference and I encourage you to come. Like my columns and its readership, the conference is mostly technical in nature and the audience is composed mostly of professional X programmers.

As with any technical conference, you'll get more out of it if you study a little before hand. This preparation will help you to understand both the technical content of the individual presentations, and, perhaps more importantly, the trends and issues that affect the industry as a whole. To help improve your experience at the conference, this month's Advanced Application Programming will review some of the technical issues that I think will be important at this year's X Technical Conference.

The material is my personal opinion, of course. You may feel that I am incomplete or incorrect. You may even be right. Fortunately, the interactive nature of technical conferences like this helps all of us discuss and better understand the issues.

Issue 1: The World Wide Web

Most of us will agree that the hottest computer technology of 1995 was the World Wide Web. We may disagree about its goals and its future, but it certainly did get everyone's attention.

In many ways, the X Window System and the World Wide Web are very similar:

Note that the Web is now in a similar position to where X was when X11R1 first came out: it has a lot of promise, but the lack of tools and standards limit its usefulness in complex applications.

At the X Conference, you should look for three areas where the X Window System meets the World Wide Web:

You'll probably see a lot more in each of these areas over the coming years.

Issue 2: Loadable and Plug-In Objects

Another important technology is loadable or plug-in objects. These objects are essentially function libraries that running programs can specify and load at run-time. Unlike shared libraries, loadable objects need not be compiled into or linked with the main program.

In most cases, the main program defines a specification for the loadable objects and the objects themselves are later developed to meet the specification. Since the loadable objects can be implemented (and shipped) independently from the main program, they allow the main program to be easily and continually updated to meet changing user needs.

Loadable objects have been popular with X server developers for several years. X servers are generally implemented using a device-independent X layer (DIX) and a device-dependent X layer (DDX). Some vendors that support a variety of display hardware (and thus a several different DDX layers) have found that a useful design is to implement the DDX layers as loadable modules. When a new display device is shipped, the vendor need only ship a new DDX module. The existing DIX layer will load the DDX module at run-time.

The same concept can be used in applications. For example, an image processing application could use loadable objects to read and write image files of with different file formats. To support a new file formats, the application developers would only have to ship new file format loadable objects. They could even encourage their customers or other companies to develop custom objects for specialty formats.

Since most UNIX-based operating systems now support loadable objects, I think you'll be seeing more products with this sort of open, extensible framework. Several of the conference presentations discuss projects that use frameworks like this, including mine[Lee].

Issue 3: Multimedia

Multimedia has been an important topic to the X community for several years. This year is no different. Several papers at the X Conference discuss multimedia, including:

If used well, multimedia can add a whole new dimension to your applications' user interfaces. Look especially at the integration issues, including:

Issue 4: High Quality Graphics

Like multimedia, the area of high-end graphics has also been a long time issue in the X Window System community.

The core X protocol supports only simple line graphics. As computers get faster and cheaper, however, more users have become interested in 3D graphics, graphics animation, etc. The X community seems to be converging on OpenGL as the X-based 3D graphics system of choice. There are several presentations on OpenGL this year, but none on the once popular PHIGS, PEX, or GKS.

Issue 5: The Common Desktop Environment (CDE)

Most of the UNIX industry is also settling on CDE as the X-based graphical desktop framework. CDE provides interesting services for application developers such as resource management, session management, file management, a help system, a printing system, and a GUI style guide.

There will be two tutorials on CDE at the conference.

Issue 6: GUI Testing

The technologies I've discussed above will help to improve the functionality of your applications' user interfaces, but they may also make your user interfaces more complex and more difficult to test.

Fortunately, several groups are working on GUI testing methodologies and tools. This year's X Conference includes several tutorials, presentations, and BOFs on testing.


Hopefully, this material has given you some idea about what to look forward to at the X Technical Conference. The conference can be a very rewarding experience for X application developers.

You can learn a lot from the proceedings[Proceedings], but the conference itself offers much more to the attendees. While the proceedings do include papers from most of the technical presentations, they do not include any of the demonstrations or discussion that took place during the presentations. They also do not include notes from the tutorials or BOF discussion sessions.

By attending the conference, you can meet and interact with your fellow X programmers. The BOF discussion sessions, in particular, encourage wide ranging discussions both with fellow developers and with technical experts. If you've been unable to solve a particular problem, you should be able to find plenty of help at the conference.

The X Conference is also a great place to look for new job opportunities or to find for top-notch candidates to fill your openings: bring your resumes and want ads.

I'll giving a talk on some of my recent work at the Wednesday morning presentation session. I hope to see you there.


Kenton Lee, MediaWarehouse: Integrating Multimedia with the X Window System Desktop, to be presented at the X Consortium Technical Conference, February, 1996.
X Consortium, Proceedings of the 10th Annual X Technical Conference. The proceedings are published by O'Reilly & Associates, Inc. a special issue of The X Resource journal.

Ken Lee is an independent software consultant specializing in X Window System application software. He has been developing UNIX graphical user interface software since 1981. Ken may be reached by Internet electronic mail at kenton @ or on the World Wide Web at

Ken has published over two dozen technical papers on X software development. Most are available over the World Wide Web at