UpFront

diff -u: What's New in Kernel Development

Zack Brown

Issue #132, April 2005

Linus Torvalds and Andrew Morton are still trying to find the best way to continue developing Linux. With the death of the idea of a stable/unstable series, there is still a push toward stability for each actual point release, such as 2.6.9 and 2.6.10. However, many users are reluctant to test the 2.6 kernels because of the tremendous amount of development going into them. Linus, Andrew and others have been giving thought to how to attract more testers to the now unpredictable official tree. One idea has been to bring back the stable/unstable concept for alternating versions. So 2.6.11 would be a stabilization kernel, with only bug-fixes for a couple of months, while 2.6.12 would be a new-feature kernel for a couple months, and so on. Another possibility would be to add a fourth number to the version, with numbers like 2.6.11.2 and 2.6.11.3, and these releases would be used for bug-fixes, while more development takes place on 2.6.12. So far nothing is certain, and Linus and Andrew are still trying to figure out the impact of abandoning the original stable/unstable development system. Stay tuned.

An interesting copyright question arose when Adrian Bunk noticed that ReiserFS files included a notice implicitly transferring copyright of all additions to Hans Reiser. The authors of the code explicitly could retain copyright by including text with their contributions, but Adrian felt there was something fishy about it. Linus Torvalds has given his support to Hans' copyright handling, and Hans himself also makes a point of asking all contributors directly, for the copyright assignment. According to Hans, the text is only in the source files in order to cover his backside from the likes of The SCO Group. And as Christoph Hellwig has pointed out, SGI makes the same request for copyright assignment from anyone contributing to the XFS filesystem. With precedent, politeness and an affirmation from the top Linux dog, it's possible this practice may spread to other areas of the kernel as well.

Marcus Metzler noticed that iRiver had released a binary-only product based on Linux and had refused to release any source code along with it. They certainly have made no secret of the fact that their multimedia player is Linux-based in their publicity and manuals, but no copy of the GPL, nor any offer to provide sources, have been found on their site or in their product.

The SquashFS compressed filesystem hovers on the brink of acceptance into the official kernel tree. Phillip Lougher's code is self-contained, functional and clean. Folks like Greg Kroah-Hartman have been urging him to submit the code, but Phillip is reluctant. He has many new features to add, and whether it would be best to implement these before or after acceptance into the official kernel is not clear to him. I think it is a safe bet that SquashFS will have no trouble getting into 2.6, whenever Phillip decides the time is right. The kernel dudes eagerly await his submission.

FUSE, on the other hand, a user-space filesystem actively trying to be accepted into the main kernel tree, is running into serious problems. Linus Torvalds, in particular, believes that filesystems simply are not supposed to be user-space creatures. Divorcing a filesystem from the kernel, he says, is the same as microkernels' attempt to split the guts of a system into discrete pieces. For the same reason that Linus believes in a monolithic kernel structure, he believes that a user-space filesystem is a bad idea. On the other hand, Linus has said he'd be willing to accept FUSE, with a restricted feature set, if it avoided certain ugly behaviors that he feels should not be the province of a user-space filesystem anyway. He had a similar set of restrictions with DevFS long ago. The DevFS situation turned into a mess, partly because the /dev directory is so central to Linux. A single filesystem probably will be nowhere near as controversial.

A Hot New Linux PXA

Doc Searls

Issue #132, April 2005

The coolest Linux product I saw at CES 2005 (the giant Consumer Electronics Show in Las Vegas—for more, see Linux for Suits on page 46) was the new Archos PMA430 Pocket Media Assistant. Because you can stick just about any noun you want between “Personal” and “Assistant”, let's call it a PXA. It's less than an inch thick, 3.1" wide, 4.9" long and just under 10 ounces.

Because it's Linux, open source and a member of nobody's media management silo, it's free to do all kinds of stuff that Apple, Sony and other handheld makers with lock-in agendas will never support on their own devices. For example, it will record digital audio as well as play it back, which it can do in Ogg Vorbis as well as MP3 and other formats. It will record and play back digital video (MPEG-4 SP on a 3.5" 320x240 screen). It's a full-featured PDA, using Qtopia software, and a photo viewer with a 30GB hard drive that also serves as a peripheral storage volume through USB 2 or USB 1. It has ten hours of battery life playing audio and about half that playing video. It runs games. It has built-in Wi-Fi and an Opera browser. Best of all, it's open to anything written for its Linux OS. To that end, the company plans to have a software development kit released by the time you read this.

Bastet: fph.altervista.org/prog/bastet.shtml

Don Marti

Issue #132, April 2005

Everyone likes a nice game of Tetris every now and then, but what about an evil game of Tetris? Frederico Poloni's Bastet, short for Bastard Tetris, is a Tetris clone that picks the worst possible piece to fit into your stack. It's based on petris by Peter Seidler and has a lean, mean interface. No music and no fancy graphics, only the bastard AI and you.

Whether you're working on your Tetris game and hoping to go pro, celebrating the 20th anniversary of the original Tetris, or simply looking for an implementation that will make you lose and get you back to work sooner, this is a game to try.

On the Web

Being a publication ourselves and a part of a company that has published books, magazines and Web sites, we're always interested in what is happening in the world of publishing. Based on the following Web articles, available on the Linux Journal Web site, one of the newest trends is moving publications toward an open-source model:

  • This issue's EOF discusses how the open-source paradigm is being applied to scientific publishing to encourage equal access to information published in scientific journals. Author Christopher Frenz explains how this growing movement led to the National Institutes of Health (NIH) asking that published research results funded by NIH be released without cost after a period of six months. In his Web follow-up article, “Voice Your Opinion to the NIH” (www.linuxjournal.com/article/8061), Frenz outlines how you can let the NIH know your thoughts about open access for science.

  • As Clay Dowling explains, however, open-source publishing models are not being investigated and used only for science. “Publishing Open-Source Documents with Open-Source Tools” (www.linuxjournal.com/article/8062) describes the entirely open-source process and tools used to produce The Shadow of Yesterday, written by Clinton Nixon of Anvilwerks (www.anvilworks.com). Dowling and Nixon also discuss “the practical business impact of publishing an open-source document with open-source tools”.

Do-It-Ourselves Media

Doc Searls

Issue #132, April 2005

Take Creative Commons, Internet Archive, podcasting and the video edge of the blogging movement; then, combine it with a do-it-ourselves attitude. The result is ourmedia, which founder J.D. Lasica (author of the new book Darknet) calls “an all-volunteer, open-source media project”. Or, in the words of its slogan, “The Global Home for Grassroots Media”.

ourmedia is an excellent example of non-programmers and programmers getting together and creating a new infrastructure that's based on open-source principles and attracts the participation of both open-source programmers and free-range digital creators of all types.

Marc Canter, perhaps best known as the driving force behind Macromind, which later became Macromedia, is another of the leading figures in ourmedia. His company is Broadband Mechanics, which also is involved with ourmedia. Marc says, “Our business model is to help create and promulgate new standards—and then build on top of them.” Other partners in the project are Bryght, Creative Commons, Wikipedia and The Internet Archive.

He also draws a distinction between standards based on companies and those based on independent open-source efforts that operate outside any company's platform-based silo. “If Google, eBay and Amazon can be infrastructure for Web 2.0, why can't we build our own infrastructure? This is just one of the first of many projects.”

The site is Drupal on Linux, naturally. ourmedia volunteer programmers are leveraging other open-source tools to make it easy for nontechnical folks to upload and share their works in the free (as in beer and speech) and wide-open spaces provided by the Internet Archive.

According to cofounder Marc Canter, the first handy hack uses Python to build an uploading tool based on Creative Commons' The Publisher, a graphical desktop application that attaches licenses to audio and video files and uploads them to the Internet Archive. “We're taking the source for that tool and extending the metadata to all media types, not just audio and video. And we're pointing it to the ourmedia collection, where each file will have its own location and will be easy for anybody to find as soon as it's up there. Everybody will also have their own ourmedia page, with a listed history of every file they've published, ready for Creative Commons-licensed use. This makes them a) part of a community and b) able to keep track of the files they've published and show that list of published stuff to others.”

He adds, “Of course you can still ftp to the same directory, but how many artist types will know how to do that? This tool will let the artist upload large files directly without going through HTTP.”

To get involved, visit ourmedia.org.

Ten Years Ago in Linux Journal: April 1995

Don Marti

Issue #132, April 2005

Kurt Reisler wrote that the Digital user group DECUS was planning a half-day seminar led by Linus Torvalds at its May 1995 conference, plus a full day of other Linux activities. Looking forward to the Digital Alpha port of Linux, he wrote, “Imagine your Linux system running at 300+ MIPS.”

The transition from a.out to ELF shared libraries was in progress, and the issue covered both. Eric Kasten wrote a shared library tutorial, including how to create the then-current a.out format. “The current a.out shared libraries will probably need to be supported for some time”, he wrote. Meanwhile Eric Youngdale contributed an introduction to ELF, including the reasons we were all switching to ELF.

Joesph Brothers wrote a tour of hardware architectures with Linux ports. At the time, only x86, Motorola 68k and Alpha would run a shell. Others in progress were MIPS, SPARC and PowerPC. Alpha was the BogoMips champion at 149.49. The “bogo-fastest” x86 listed was a 486DX4/100 at 50.08.

Pacific Hi-Tech advertised the “Linux Run-Time System 1.0”, a live CD distribution that booted and ran without installing to the hard drive, for $29.95 US.

They Said It

Only understanding for our neighbors, justice in our dealings, and willingness to help our fellow men can give human society permanence and assure security for the individual.

Powerful, reliable software and improved technology are useful byproducts of freedom, but the freedom to have a community is important in its own right.

The GPL is the most popular license for free software....As of April 2004 the GPL accounted for 74.6% of the 23,479 projects with an OSI-approved open-source license listed on Freshmeat. The GPL also accounted for 68.5% of the 52,182 free or open source software projects listed on SourceForge.