April 2007

Military27 Apr 2007 at 10:33 by Jean-Marc Liotier

This week, the BBC published a photographic essay about the ongoing fighting between Ethiopian-backed forces and insurgents in the Somali capital, Mogadishu. One of the notable features of this battle has been the mortar bombardment, so inaccurate that it could as well as been random. The insurgent from the Hawiye clan and the islamic militias remnants of the Islamic Courts of Somalia have been accused of terrorism, but I have a alternate theory.

Hanlon’s Razor teaches us to never ascribe to malice, that which can be explained by incompetence. Among the pictures in the essay was the following one. Take a good look at it :

Notice anything remarkable ? Does not the blue round look a bit odd if just from the perspective of chromatic harmony ? Actually it is much worse than that, and those among you with some military culture are probably laughing already.

For those not familiar with ordnance color codes, the color blue is the convention for marking inert training rounds. Those rounds are designed to give crews practice in firing and technique of fire without the expense incident to firing HE ammunition. On impact, the practice rounds emit a puff of white smoke. Those round differs from the HE version in color and filler only.

The Ethiopian army and the Darod on the receiving end are surely going to believe in miracles when they are still alive after that mortar round impacts among them in a rather harmless puff of white smoke.

What is that training round doing among live ones is anyone’s guess. If anyone tells the shooters, you can be sure that whoever holds the mortar ammunition stall at Bakara market will at least have to offer them a discount on their next purchase of ordnance…

Systems26 Apr 2007 at 16:23 by Jean-Marc Liotier

Under Microsoft Windows XP, a PDF file displayed well, but when I ordered the viewer to print it crashed abruptly. I reproduced the problem with Adobe Acrobat Reader, both standalone and embedded into Mozilla Firefox. I also reproduced it reliably using Foxit Reader. I was puzzled that both programs would crash in the same way, and even more puzzled that they would do it with a variety of PDF files.

As I found out, PDF renderers are apparently very picky about printer drivers. I tried printing to a different printer and the document came out fine.

The interested reader may also want to investigate the influence of font embedding on this problem. I have not performed any tests about it but I suspect it might be interesting to check if any link can be established.

Debian and Email and Systems25 Apr 2007 at 16:40 by Jean-Marc Liotier

I upgraded the Sympa mailing list manager to 5.2.3-2 using the Debian package from the “Testing” repository. The database part of the upgrade procedure was a bit fussy so instead of solving its problems I simply backed up the tables, dropped them, ran the upgrade procedure and restored them. That workaround worked fine for making the Debian packaging system happy.

But Sympa itself was definitely not happy. On starting Sympa I got the following logs in /var/log/sympa.log :

Apr 25 17:02:39 kivu sympa[657]: Could not create table admin_table in
database sympa : Table ‘admin_table’ already exists
Apr 25 17:02:39 kivu sympa[657]: Could not create table user_table in
database sympa : Table ‘user_table’ already exists
Apr 25 17:02:39 kivu sympa[657]: Could not create table subscriber_table
in database sympa : Table ‘subscriber_table’ already exists
Apr 25 17:02:39 kivu sympa[657]: Could not create table netidmap_table
in database sympa : Table ‘netidmap_table’ already exists
Apr 25 17:02:39 kivu sympa[657]: Unable to execute SQL query : You have
an error in your SQL syntax; check the manual that corresponds to your
MySQL server version for the right syntax to use near ‘.`admin_table’ at
line 1
Apr 25 17:02:39 kivu sympa[657]: Database sympa defined in sympa.conf
has not the right structure or is unreachable. If you don’t use any
database, comment db_xxx parameters in sympa.conf
Apr 25 17:02:39 kivu sympa[657]: Exiting.
Apr 25 17:02:39 kivu sympa[657]: Sympa not setup to use DBI

With no database access, Sympa was not operational. Double plus ungood !

The very strange thing is that the database is fine : the right tables with the right fields and the right records are all present. It even worked with the preceding version of Sympa. It looked like Sympa itself was unable to recognize that my database setup was correct, subsequently reported those errors and thereafter refused to run with it at all.

With a little rummaging inside the Sympa-users mailing list I quickly found a report of something looking suspiciously like my problem. It is probably a bug and Olivier Berger proposed a patch that looked to me like a workable solution : according to Olivier, a faulty regex was the cause of Sympa‘s failure to recognize it’s own.

After making a backup copy of /usr/lib/sympa/bin/List.pm I promptly applied his patch :

17:04 root@kivu /usr/lib/sympa/bin# diff List.pm.dist List.pm
> $t =~ s/^([^.]+\.)?(.+)$/\2/;

I restarted Sympa and it worked fine ever after. Thank you Olivier !

The only problem is that while Sympa was down, people wondered why the messages did not go through and resent some of their messages. None of those messages were lost – they were just piling up in a queue. So when Sympa restarted many duplicates were sent.

But at least now it’s working. So for now I’m going to use dselect to freeze the Sympa Debian package at its current version so that it is kept back next time I upgrade my system.

Email and Knowledge management20 Apr 2007 at 9:31 by Jean-Marc Liotier

Last year when I reviewed the IMAP keyword tagging scene, I said :

Thunderbird supports IMAP keywords but only allows five of them. This is a known bug but it has been open for more than four year so I’m not holding my breath for it. The amount of comments made to that bug show that user expectations about IMAP keywords are slowly growing.

Eager taggers rejoice : your wishes have been heard… Among the feature list of the just released Thunderbird 2 I read :

Thunderbird 2 allows you to tag messages with descriptors such as “To Do” or “Done” or even create your own tags that are specific to your needs. Tags can be combined with saved searches and mail views to make it easier to organize email.

This is exciting because last year I was pleasantly surprised to see both IMAP servers and MDA providing apparently mature support for IMAP keywords, but I concluded that we were just some client support away from being able to use them.

So the the last missing piece of the IMAP mail tagging puzzle may have been delivered and I shall soon play with it to see if it lives up to its potential.