Cybernethics / Cybernéthique

You may remember that I am looking for a solution to the SNAIL problem, which will have to be based on epistemic monotonic logic. Well, monotone offers half of the solution, monotonic logic. And that is also the more useful half to me, considering that the instantaneous latency of my SNAIL networks is actually low: when my computers are connected to each other, then the communication latency between them is below a few tenths of seconds at most.

My friend Mahesh had this PB3400c with 80MB of RAM and 2.5GB of harddisk, that he wanted to transform into a jukebox. A few weeks ago, he asked me to install Linux on it, to play music off the network, and so I did. I learnt much more than I ever wanted to know about Macs, in the process, yuck, but it's incredible how Linux can turn an old computer into something able to use the latest intercommunication standards to do useful things. Here are steps to follow if you too want to install Debian GNU/Linux on a similar computer.

Now that I have a newly working Lisp development system running Debian, complete with XEmacs, CLISP, SLIME, SSH and CVS, I have taken time to publish my Common Lisp software in the updated form of asdf packages, ready to be installed with asdf-install. Yup, that packaging software is named ASDF. Not SHRDLU.

I may have been out of the loop, but I was happily surprised to see how Linux was present everywhere during my air travels. First thing, I hear Dell spending several minutes in an on-flight radio program explaining how it installs RedHat Linux on its servers, or whichever other flavor of Linux suits their customers. Next thing, Oracle bought all the ceiling ads in SEA airport to say that Oracle makes Linux unbreakable. In San Francisco, Veritas puts Windows, Unix and Linux on par. Finally, on my trip back, the in-flight entertainment system by Panasonic reboots in Linux: I could see the penguin on my neighbour's screen as he desperately twiddled the command pad. Wow. Linux has gone a long way in thirteen years. The free market works around information protectionism, slowly but surely.

The Linux framebuffer console for the Jornada820 and other machines does not heed all the cursor controls that it has on the x86 console. Therefore, many programs that try to reprogram the cursor, including the login program and emacs, end up making the cursor invisible. A correct escape sequence to make the cursor appear, as per the Framebuffer-HOWTO, is ESC [ ? 2 c (thank you once more, pineal gland). Now, my problem, is to convince Emacs to output this control sequence instead of the one it uses to program the cursor, or sometimes after it makes the cursor invisible, so as to ensure the cursor is visible. Can any (X)Emacs guru out there help me find out how?

Yes, of course, an alternative take would be to edit the framebuffer driver and fix it so it works as advertised, or at least doesn't make the cursor invisible unless explicitly requested. However, I'd also like to convince Emacs to output other control sequences when it initializes its output: for instance, I sometimes found the console in the wrong output encoding mode, I'd like to ensure latin1 output encoding with the ESC ( ? B control sequence. The scary thing is I remembered enough of this sequence to retrieve it by testing things on the console, since I had spent quite some time fixing the same issues on a PC. (that is, I remembered ESC something, ( something and an uppercase letter.) My experimentation included the writing of a shell script to display those characters in the ASCII table that are not control codes; the script takes several seconds to run, spawning three subprocesses at every character, and using eval. Ain't Unix a wonderfully designed operating system? I don't think so. Just because I may prefer Linux to its current competition doesn't mean I'm not more and more of a Unix-hater.

( Read more... ) in the big mansion of the uncle who hosts me, with the WiFi router in a central location, I could walk around the whole house with my other uncle's iPAQ 5555, and stay connected to the Internet the whole time through ( Read more... )

Yay, the Jornada 820 can now be used for good under Linux. Big thanks to George Almasi who got the console and PCMCIA to work! A lot of work remains to do, but that's significant progress.

Dans le cadre du LLLC, je donne des cours d'introduction à Linux. Voici le brouillon de mes notes de cours. Avez-vous des suggestions pour les compléter?