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Apparently the people who run the keyserver have no clue.

The Linux-Ecology-HOWTO discusses ways to make computers less harmful to our environment and to solve some ecological issues. It explains how to use Linux to save power and consumables like paper and ink. Since it does not require big hardware, Linux may be used with old computers to make their life cycle longer. Games may be used in environmental education and software is available to simulate ecological processes.

The best collection of geeky humour I have seen is Thomas Baetzler's Humor on the Internet.


Researchers have devised a penny-sized silicon chip that uses photons to run Shor's algorithm - a well-known quantum approach - to solve a maths problem.


On2 Technologies seem to have been behind lots of major video codecs. VP3 became the basis of Theora, VP6 was selected for use as the Macromedia Flash 8 video codec, and they claim that their VP7 is superior to the recent H.264/AVC standard. Google recently announced that it will buy On2 Technologies for $106.5 million.


Great news for coreboot fans - AMD has released documentation for the SB700 chipset family and the RS780 family of integrated chipset/graphics processors.

Tim Bray noticed that the XML entry in Wikipedia was appallingly bad, so he took it upon himeself to fix it. Others chipped in and although it could still do with further work he is reasonably pleased with it now. See his blog entry Fixing XML.


A zero-day vulnerability in Flash is being exploited in the wild using malicious PDF documents. The exploit takes advantage of a new feature that Adobe introduced in Acrobat 9, which allows the embedding of Flash media content in PDF files.


Dave Dribin compares distributed version control systems, Git, Mercurial and Bazaar.


Source code that ran on the Apollo 11 spacecraft has been transcribed from scanned images and made available for the Virtual AGC Project.


John Gruber has a great article on his Daring Fireball site - Putting What Little We Actually Know About Chrome OS Into Context.

Ceph is an open source distributed file system capable of managing many petabytes of storage with ease.


When Google came out with their own browser (Chrome) it was widely suspected to be the first stage in their development of a Google operating system. Lo and behold - Introducing the Google Chrome OS.


Computer chipmaker Intel has been fined a record 1.06bn EUR by the European Commission for anti-competitive practices.


Experts from more than 30 US and international cyber security organizations jointly released the consensus list of the 25 most dangerous programming errors that lead to security bugs and that enable cyber espionage and cyber crime.


A few years ago I read something about using trailing whitespace to hide messages in within text files, but someone has just reminded me about it so here is the link to SNOW.


Roger Alsin has generated a lot of interest over his Evolution of Mona Lisa using a form of genetic programming to develop a good likeness of the Mona Lisa using a relatively small number of polygons.


Make Magazine has a good guide to Arduino starter kits.


I just read David Roundy's theory of patches which is the basis of his distributed revision control system called darcs.


Rands in Response: Dumbing Down the Cloud.


Mobile phone chip designer Arm has announced an alliance with the makers of the Ubuntu open source software.


Meggy Jr RGB is a handheld platform for developing your own pixel-scale video games. It is designed to be programable using the Arduino software environment.


The TCP/IP Guide is a reference resource on the TCP/IP protocol suite that was designed to be not only comprehensive, but comprehensible.


Computer criminals could soon be eavesdropping on what you type by analysing the electromagnetic signals produced by every key press.


Seeds for Change have some useful resources relating to Computers and Linux, including a Computer Security Postcard Guide which can be downloaded as a PDF.


GrokCode has an interesting analysis of 222 famous programmers from Adleman to Zimmermann.


A press release on the ISO website today announced that all the OOXML appeals have been directed and that at some point in the future some sort of "standard" will be published - a standard that nobody (not even Microsoft) is currently using because nobody knows what it will be. It can't be the standard that was submitted because that was riddled with problems that were not solved at the BRM - the ISO has lost all credibility over this, particularly amongst developing nations that have been spectacularly ignored.


Command Line Warriors have just published part one of a piece about native XML storage with Berkely DB XML. It mentions a good 2005 article by Eliotte Rusty Harold called Managing XML data: Native XML databases.


Command Line Warriors choice of top ten mailing list posts in the history of free/open source software.


Matasano is an independent security research and development firm - lots of intersting stuff on their website.


Hackontest is a 24 hour programming competition between teams of three open source software projects. The event takes place at OpenExpo on September 24/25, 2008 in Zurich, Switzerland.


Back in 2006 I gave a link to a page about trinary computer systems. That page still exists but is no longer updated, content having been moved to Jeff's Trinary Wiki. There are some pages on Wikipedia about this stuff but it is referred to as ternary rather than trinary - see for example Ternary logic.


Richard Stallman will be presenting a talk on "Free Software in Ethics and Practice" at the University of Manchester on May 1st. It is a free talk and apparently there is no need to book a place - "just turn up on the night".


Someone just emailed me a link to a funny and interesting talk by Jason Dixon called BSD is Dying A Cautionary Tale of Sex and Greed, which he presented at the NYC BSD Conference 2006.


I did once make a brief foray into the world of Emacs but I am basically a Vi guy, like the man hiding from the cops in the cartoon that illustrates this useful comparison of Emacs and Vi.

Parsing expression grammars (PEGs) are an alternative to context free grammars for formally specifying syntax, and packrat parsers are parsers for PEGs that operate in guaranteed linear time through the use of memoization.


Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.


Today is Document Freedom Day.


Toshiba has said it will stop making its high definition DVDs, ending a battle with rival format Blu-ray over which would be the industry standard.

Some of the world's biggest computer firms have been accused of imposing unfair contracts on customers who buy their software.

POVRay is a free ray tracing application which can be used to create amazing images - here are the winning entries from the POVRay short code contest number five.


I have mentioned the Xen virtual machine monitor a couple of times on this page. I just found out that on 2007-10-22, Citrix Systems completed its acquisition of XenSource and the Xen project moved to a new website.


On January 11th, Ron Minnich announced that LinuxBIOS has changed its name to coreboot.


HD DVD backers reeling as Blu-Ray shines at electronics show.


Erlang is a general-purpose concurrent programming language and runtime system.

I recently heard a radio interview with Tom Perkins who I had not previously heard of. He has been incredibly influential in the computer world, being closely involved with both Hewlett-Packard and Compaq. Unfortunately he currently sits on the board of directors of the Dirty Digger's News Corporation.


From Rainbow Hash Cracking posted on Coding Horror:

The multi-platform password cracker Ophcrack is incredibly fast. How fast? It can crack the password "Fgpyyih804423" in 160 seconds. Most people would consider that password fairly secure. The Microsoft password strength checker rates it "strong". The Geekwisdom password strength meter rates it "mediocre".


The Wolfram 2,3 Turing Machine Research Prize has been won by 20-year-old Alex Smith of Birmingham, UK.


If there is a bug in a microprocessor which results in there being even a single pair of integers whose product is computed incorrectly (even in a single low order bit) then any key in any RSA-based security program running on that processor can be trivially broken with a single chosen message.


An amateur cryptographer has beaten Colossus in a code-cracking challenge set up to mark the end of a project to rebuild the pioneering computer.


A blast from the past here. Back in 1999 Tim O'Reilly published Ten Myths about Open Source Software.


Acting on the advice of the License Approval Chair, the OSI Board today approved the Microsoft Public License (Ms-PL) and the Microsoft Reciprocal License (Ms-RL). The decision to approve was informed by the overwhelming (though not unanimous) consensus from the open source community that these licenses satisfied the 10 criteria of the Open Source definition, and should therefore be approved.


Over a third of a million visitors have attempted to solve the Python Challenge since May 2005.

Here is a free PGP Digital Timestamping Service.

QEMU is a generic and open source machine emulator and visualiser.


Tim Bray is Following the OOXML Story.


I just read an article by Steven Poole - Goodbye, cruel word, A personal history of electronic writing.


Russell Beattie explains why Java needs an overhaul.


Plans are taking shape to set up a museum that celebrates Britain's role in the origins of the digital age.

2007-07-08 is the home of E, the secure distributed pure-object platform and p2p scripting language for writing Capability-based Smart Contracts. I found it referred to in this excellent Introduction to Capability Based Security and I liked this quote:

A fully paranoid actor should indeed assume the entire world is a monolithic conspiracy against them. Only with some trust that parts of the world are independent can we gain evidence of any other hypothesis.


From What Colour are your bits:

There's a classic adventure game called Paranoia which is set in an extremely repressive Utopian futuristic world run by The Computer, who is Your Friend. Looking at a recent LawMeme posting and related discussion, it occurred to me that the concept of colour-coded security clearances in Paranoia provides a good metaphor for a lot of copyright and intellectual freedom issues, and it may illuminate why we sometimes have difficulty communicating and understanding the ideologies in these areas.


Amazon are already listing a new O'Reilly book called Beautiful Code: Leading Programmers Explain How They Think. I guess Brian Kernighan is the most famous contributor but I expect many of the other contributions are very well worth reading for anyone who appreciates beautiful code.


Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library. It can read markdown and (subsets of) reStructuredText, HTML, and LaTeX, and it can write markdown, reStructuredText, HTML, LaTeX, RTF, DocBook XML, and S5 HTML slide shows. Pandoc's version of markdown contains some enhancements, like footnotes and embedded LaTeX.


From the Ken Thompson Wikipedia entry:

In 1983, Thompson and Ritchie jointly received the Turing Award for their development of generic operating systems theory and specifically for the implementation of the UNIX operating system. His acceptance speech, "Reflections on Trusting Trust" presented the backdoor attack now known as the Thompson hack, and is widely considered a seminal computer security work in its own right.

I haven't made the effort to properly understand it, but if you want to have a go then here is Reflections on Trusting Trust.


More interesting stuff on ODF and OOXML in Life is Complicated on Tim Bray's blog.


Windows Vista apparently disables high quality audio and video while playing "protected content" unless the graphics or audio hardware is specifically designed to work with the insane Windows Vista content protection system. If a graphics card manufacturer wants their hardware to work with Vista they will have to make it more complex than it would otherwise need to be (see Peter Gutmann's cost analysis). It seems like what is needed are hardware manufacturers willing to produce devices that do not attempt to work with Vista, but are instead targeted purely at open systems. Although production volume would initially be small, the devices would also be simpler and not have to jump through the Microsoft hoops. The manufacturers would also not have the cost of driver development since they could release full hardware specs and leave driver writing to the community. Fortunately this is already in hand, and the Open Graphics Project have already got as far as producing a prototype board.


A paper called Keyboards and Covert Channels was presented at the 15th USENIX Security Symposium. This paper introduced "JitterBugs", a class of inline interception mechanisms that covertly transmit data by perturbing the timing of input events likely to affect externally observable network traffic.


OpenXML wrap-up after D12K is a great roundup by George Greve of some of the issues raised since the recent disturbing ECMA approval of Microsoft's so called standard.


I have just been reading some stuff from the computer memory category on Wikipedia - particularly the stuff about obsolete computer storage media.


Yesterday, ECMA approved Microsoft's Office XML "standard" despite objections from IBM. This is a mixed blessing - on the one hand it should allow for greater interoperability with Microsoft Office (which is of course currently the dominant commercial office application suite) but on the other hand it is bound to set back adoption of ODF - the true standard XML-based file format for office documents. Office XML is insanely complex compared to ODF (the "standard" is over 6000 pages compared to about 700 for ODF) - due to the fact that it is designed specifically for compatibility with Microsoft Office rather than from a (relatively) blank sheet. Based on an article by Rick Schaut of Microsoft's Mac BU, Andrew Shebanow estimates that it would take about 150 man-years to implement Office XML support for a competitive product! That is fine for the likes of Novell who have the resources and will receive financial and technical help from Microsoft, but it is a hell of investment to make.

The boom in cyber crime is forcing criminals to go to great lengths to recruit skilled hackers, says a report.


Novell - forking itself out of the FOSS community?


On the Power of Simple Branch Prediction Analysis shows how a carefully written spy-process running simultaneously with an RSA-process, is able to collect during one single RSA signing execution almost all of the secret key bits.


Java is Free


DVD Jon is in the news again regarding plans for a company called DoubleTwist to release a commercial version of his QTFairUse program which unlocks music purchased from the iTunes Music Store.


A couple of years ago I read up some stuff about the experimental Eros Operating system which seemed pretty cool. The project is no longer active but the work is being continued in other projects. One of the main distinguishing features of Eros was that it implemented Capability-based security. In 1999, Jonathan Shapiro wrote an excellent introduction to capabilities called What is a Capability, Anyway?.


Check our Master Foo and the Ten Thousand Lines as an example of one of esr's Unix Koans.


Rob Enderle is at the IDF (Intel Developer Forum) this week and has posted a report on tom's hardware guide.


Here is an FSF response to some of the criticisms mentioned in the position paper I mentioned in my last entry. For me, the contentious paragraph in the FSF response is:

GPLv3 will prohibit certain distribution practices which restrict users' freedom to modify the code. We hope this policy will thwart the ways some companies wish to "use" free software -- namely, distributing it to you while controlling what you can do with it. This policy is not a "use restriction": it doesn't restrict how they, or you, can run the program; it doesn't restrict what they, or you, can make the program do. Rather it ensures you, as a user, are as free as they are.

As I understand it the "certain distribution practises" being alluded do not actually "restrict users' freedom to modify code". They do restrict users' freedom to run modified code on the hardware with which the original code was shipped, but that is not quite the same thing.


About a week ago, ten Linux kernel developers released a position paper about dangers and problems they see with GPLv3.


I was searching for stuff about base three arithmetic and cam across an excellent page about Trinary Computer Systems.


64-Bit Programming Models: Why LP64?


I can can hardly believe a year has gone by so quickly, today is the not-entirely-serious Annual System Administrator Appreciation Day.


Tim Bray has written a good piece about his initial impressions of Ruby.


The Lemon program is an LALR parser generator which takes a context free grammar and converts it into a subroutine that will parse a file using that grammar. It is maintained as part of the SQLite project.


Hackers on Planet Earth will be holding their sixth conference in a couple of weeks in NYC.


AIGLX (Accelerated Indirect GL X) is an open source project founded by the X.Org Foundation and the Fedora Core Linux community as an effort to simplify graphics rendering through use of modern hardware and software.

The KOffice Project has announced KOffice version 1.5 with ODF as it's native file format.


Check out what Linus Torvalds has to say about EFI (Extensible Firmware Interface).


I haven't used a revision control system since the early 1990's when I was working as a Fortran programmer. I can't remember what system we used but I have a feeling that it might have been something homegrown by the company I worked for. CVS and SubVersion are two popular revision control systems but GNU Arch seems to have lots of advantages over both.


Loud Thinking put up an article called Shaking up tech publishing which is worth a read. Make sure you look at the comments too, including excellent contributions from none other than Tim O'Reilly.


Ndiyo! is a project set up to foster an approach to networked computing that is simple, affordable, open, less environmentally damaging and less dependent on intensive technical support than current networking technology.


An open source version of the UltraSPARC T1 design has just been released under the GPL - it is called the OpenSPARC T1.


Computer viruses could be about to take a giant leap and start spreading via smart barcodes, warn experts.

Xenoppix is a customised version of Knoppix which includes the Xen virtual machine monitor and two guest OSes; NetBSD and Plan9.


Although I generally steer well clear of machines running the Microsoft Windows operating system, I have occasionally been forced to do something in Microsoft Office, and was bemused when an animated paperclip called Clippy started making suggestions. I normally do all my editing using vim, which is blissfully free of such nonsense - or is it:-)

SQLite (Winner of a Google O'Reilly 2005 Open Source Award) is a small C library that implements a self-contained, embeddable, zero-configuration SQL database engine.

FreeNX is a GPL implementation of NoMachine's NX Server.

GNotary is a set of Python scripts that implement an asynchronous digital notary service.


From an announcement by Sun Microsystems:

Sun Closes Year of Innovation with Major Global Launch of New Sun Fire Servers Powered by CoolThreads Technology; Unveils Powerful 9.6 GHz, Eight Core Microprocessor Design to Leave Competitors in Dual-Core Dust; Unveils New Purchase Programs and Plans to Open Source Processor Technology to Developer Communities.


Groklaw has some interesting OpenDocument news.

John Gruber of Daring Fireball fame is working for Joyent on a web-based system designed to facilitate collaborative working within small teams.


I was looking through some notes I took at a meeting and came across the URL for CollabNet which claims:

CollabNet is the leading provider of on-demand distributed software development solutions. Our solutions help corporations leverage the true value of their software assets by bringing together development teams, regardless of geographic location.


I just read an interesting Wikipedia article about Gary Kildall, the creator of the CP/M operating system and GEM Desktop graphical user interface, and founder of Digital Research Inc.


Many computer viruses exploit buffer overflow vulnerabilities. Aleph One wrote a good piece in Phrack 49 called Smashing the Stack for Fun And Profit which explains buffer overflows in detail.


OpenDocument, short for the OASIS Open Document Format for Office Applications, is an open document file format for saving and exchanging editable office documents such as text documents (such as memos, reports, and books), spreadsheets, charts, and presentations. The standards are developed by the OASIS consortium based upon the XML-based file format created by


Over the years I have heard a lot about VMware "Virtual Infrastructure Software" which allows concurrent running of multiple diverse operating systems on a single machine. The price of $189 for VMware Workstation 5 seems reasonable, but wouldn't it be nice to have an Open Source system to do the same thing? Well it is not quite the same, but at the University of Cambridge Computer Laboratory they have been developing something called the Xen virtual machine monitor, or simply Xen. At present it will not run Windows (unlike VMware), but they say "recently announced hardware support from Intel and AMD will allow us to transparently support Windows XP & 2003 Server in the near future".


There is a trial project in Kenya in which schools are using handheld pocket PCs to replace textbooks. It is great to see that they are using open source software.


For something slightly different:-) Someone at Sun has written a satirical bourne shell script called The War on Terror.


Here is an interesting piece about the usefulness of VMware and the big improvements that came with the recently released version 5.0.


wildmat is a pattern matching library developed by Rich Salz. Based on the wildcard syntax already used in the Bourne shell, wildmat provides a uniform mechanism for matching patterns across applications with simpler syntax than that typically offered by regular expressions.


I have not programmed in assembly language for years (6502 on a Rockwell AIM-65 in about 1980) but I just read Don't Fear the Assembler which suggests that it is easy and useful to learn on the PowerPC platform (which is what I use since my only machine is an iBook). Here are some more links that may prove useful if you take the plunge.


I just read an excellent piece by James Duncan Davidson called It's a Multi Language World which discusses the plethora of languages available for writing applications, and the fact that Java is not the answer to everything!


Although I it is not strictly for computer related projects, Paul Graham's Summer Founders Program seems like a very well thought out plan to encourage people with bright ideas to found new "startups". Your team of about three people will be paid to live in Cambridge (MA USA) for the summer with support to help get your company going.


If you are faced with a decision of whether to go for an AMD or Intel processor you may like to consider that the fact that Intel are being deliberately obstructive when it comes to enabling the use of a Free Bios, whereas AMD seem much more co-operative. See Stallman Calls for Action on Free Bios.


The Open Source Development Labs today named Samba creator Andrew Tridgell as the lab's second appointed fellow.


I was just looking through an old bookmarks file and found a link to which was an award for excellence in web design and production where the only requirement was that there should be no server side processing and that the entry should fit within 5120 bytes on the server. It has apparently been taken over by SIGGRAPH but I am not sure whether there has been much activity since 2002 when the grand prize winner was this frutiger toy by binky.


Mono is a comprehensive open source development platform based on the .NET framework that allows developers to build Linux and cross-platform applications with unprecedented productivity.


At work today I attended Mathematical Computer Science and Applications Seminar given by Michael A. Bender on the subject "Cache-Oblivious Search Trees". Michael is an excellent speaker and his talk was very interesting. His basic message is that it is often possible (surprisingly) to write an algorithm that works efficiently without any knowledge of the memory architecture (cache levels and sizes, block sizes, disk pre-fetching etc) of the host machine. His cache-oblivious search tree is based on something called a Van Emde Boas Tree. He referred to an influential paper Cache-Oblivious Algorithms by Frigo, Leiserson, Prokop and Ramachandran.

On Friday I attended a Q Associates "Low Cost Computing Seminar" at the InTechnology Briefing Centre in London. I listened to presentations from AMD, Veritas and Sun, but the most interesting for me was Topspin talking about their programmable server switches and VFrame server virtualisation software.

Sony, IBM and Toshiba have released limited data about the so-called Cell chip that is destined to be used in the PlayStation 3. IBM said it will start producing the chip in early 2005 and it will be used in general purpose computers before the PS3 is launched.


I recently read Paul Graham's excellent book called Hackers and Painters.


Poland rejects proposed EU software patents - majority now opposed.

Meanwhile, the UK Patent Office is to hold a meeting with anti-software patent activists to try to persuade them of the merits of the (hopefully now scuppered) European directive on computer implemented inventions.


Groklaw (which was my choice) has been voted grand winner of the First TechWeb Best Independent Tech Blog Readers Choice Award. Of the ten nominees, the only other one I had heard of was Slashdot, which came fourth. I have been distracted for the last half hour or so checking out second place Alice and


TechWeb received nearly a thousand nominations for its Best Independent Tech Blog award. You can vote for your favourite from the top 10, which include Slashdot and (the one I voted for) Groklaw.

Almost six years ago the International Electrotechnical Commission approved as an IEC International Standard names and symbols for prefixes for binary multiples for use in the fields of data processing and data transmission. There would be a lot less confusion if this standard were to be widely adopted.


Madduck has produced a graph of the Debian organisation in various formats.


This afternoon I attended the UH Computer Science Research Colloquium where Dr. Sven-Bodo Scholz spoke about "Functional Array Programming". He started with a brief explanation of Lambda Calculus and Functional Programming. He then spoke about his 10 years working on a functional programming language called Single Assignment C (SaC) which looks like C without a few things like pointers, but with the addition of certain carefully designed structures for representing arrays. This is "compiled" to C with a 250,000 line compiler that does a lot of clever optimisation. The language is designed to greatly simplify coding for problems which involve array operations, without sacrificing run time performance. Benchmarks indicate that performance can be comparable to hand optimised Fortran. For more information check out the SaC website.


Bochs is a highly portable open source IA-32 (x86) PC emulator written in C++, that runs on most popular platforms. It includes emulation of the Intel x86 CPU, common I/O devices, and a custom BIOS. It is capable of running most operating systems inside the emulation including Linux, Windows 95, DOS, and Windows NT 4.

The only time I have used a Version Control System was when I worked for a few months as a Fortran programmer at a CAD company in the early 90's and I can't remember much about it. I do know that one of the most widely used version control systems used these days is CVS, but I was recently reading about Subversion, which aims to be a compelling replacement for CVS in the open source community. This article on Using Subversion with XCode makes a good case for switching.


Ross Anderson leads the security group at the University of Cambridge Computer Laboratory and his home page is a mine of information.


The United Nations Development Program runs something called the International Open Source Network which is working to encourage the adoption of Free/Open Source Software (FOSS) in the Asia-Pacific Region.

Today is the first annual Software Freedom Day. Ian Gregory 2010