English language planet

Joachim Breitner Good LaTex Font Overview

I just discovered the nice Survey of Free Math Fonts for TeX and ?LaTeX (PDF-Version) by Stephen G. Hartke – a good overview of the common font packages, with examples, useful for those who have seen enough Computer Modern by now.

What I’m still missing is a good style guide: When should I use Palatino, when is Utopia a good choice? What are good reasons to use a sans-serif font for the text, and when is that not a good idea? They all look nice to me, but I doubt that the professional typographist leave it all to personal preference.

Posted Fri Dec 5 09:45:00 2008

Andrew Williams Liverpool LUG Talk

So, I finally got round to giving a talk at LivLUG, anyone who knows me will know i’m not the best public speaker in the world and I get quite nervous at the thought. It was time to grab the bull by the horns and actually do it!

My first talk was on the usage of the Wiimote within Linux, The Wiimote are very simple Bluetooth devices that can be accessed over the standard APIs with an additional library called CWiid. This allows the device to be used as a input device or as a general I/O device.

It’s quite hard to explain it in just text alone, So i’ve put my presentation on the LivLUG wiki everyone to have a look at. I recommend you grab it and give it a try yourself.

EDIT: Yes, It’s on the wiki now, but heres the direct link.

Posted Thu Dec 4 11:19:08 2008

Jean-Christophe Dubacq Why do I prefer Acrobat Reader to other free PDF readers?

I could answer this question saying that it's better, stronger, easier: that would be false. The real reason is that there exists some PDF that use advanced graphics feature of PDF that are simply not correctly implemented in other free readers.

I prefer to use free applications, as much as possible. But technical value is sometimes a strong enough incentive to switch to proprietary software, such as Adobe Acrobat Reader. Of course, I will give examples to support my claims (pictures down there). I may be mistaken, but please feel free to correct me.

Before I start, let me state that I usually use xpdf for daily work: it is fast, it makes things easy, reload is as simple as pressing "r" or changing a page. But sometimes, xpdf does not do what I would like it to do.

The linear gradient problem

The first problem comes from linear gradient rendering. In one file I did generate (this maybe the reason why the bug does appear there and not in many other places), I use a linear gradient from one colour to another. Only acrobat seems to fill the part of the gradient that is not (indeed) the gradient with the determined colors, as should be when the Extend values are set to true. The reference page is page 186 of the PDF 1.7 reference manual. Quoting from this reference: An array of two boolean values specifying whether to extend the shading beyond the starting and ending points of the axis, respectively. Default value: [ false false ].

The file is on my local disk and quite heavy, but a smaller version exhibiting the bug can be found there.

gs (and therefore gv, ggv) cannot even interpret correctly the pdf instructions.

xpdf, pdfedit, kpdf, all suffer from the same trouble.

  

Evince makes even funnier things:

Only acrobat reader does what I think it should do:

Another pain: large maps and other shadings

I do own yet another file (again, generated by me) that shows a related bug (out of gradient colorisation) and also demonstrate the pain that it is to open a large file (with not that many bitmaps, but many vectorial operations). The file is almost unreadable under xpdf at 200% resolution (it's better than it used to be at 100%, but that may be because my desktop computer uses 4 GiB of memory). Same problem with Evince and pdfedit. Kpdf could not even display the thumbnail. Acrobat reader, rendering the file incrementally, has no problems (it's slow, but works) to display it at 1600% zoom. The bug, here, is that apparently (I will not comment further on that) that free readers render the whole area in memory, even though one needs only to see a very small one. The file is small in octet size but meant to be printed on A0 paper (1 m²) and can be found there.

Posted Mon Dec 1 15:18:09 2008

Martin Albisetti Do you use bazaar? Let us know!

I bumped into the Who uses bzr page today again, and I’m impressed on how fast it grows, just a few examples:

- APT
- Drupal
- iPython
- GNU Mailman
- MySQL

Are you using it? Add yourself to the wiki!

Posted Fri Nov 28 23:32:40 2008

Martin F. Krafft Up the Khyber!

What started with a little host naming theme riddle, and spread as a meme across various planets, has come full circle today, as I installed a new machine, khyber.madduck.net in the racks hosted at the LayerOne colocation site in Zürich.

Init Seven, my favourite Swiss ISP, are sponsoring the rack space and connectivity: a routed /28 IPv4 subnet and a /64 IPv6 subnet.

The machine is a Transtec Calleo 331 1U server with two quad-core AMD Opteron 2354 processors, 16Gb of RAM, and 4Tb of disk space, configured into a 2Tb RAID1 with LVM on top. It will be used to host a couple of KVM instances for a number of projects I currently operate off my main, personal server, pulse.madduck.net.

Unfortunately, Transtec (as well as most other vendors I checked out) uses nVidia’s MCP55Pro chipset, which had me sceptical long before I sent the order. nVidia is known to suck at thinking open-source, and the Linux kernel driver for their network chips, forcedeth, had to be reverse-engineered, because nVidia failed to cooperate. Apart from that, nVidia’s chips are also often simply crap. Many of their motherboards come with broken APICs and the network chips often wreak havoc on subnets.

I find it curious that a search for “MCP55” or “MCP55Pro” on the nVidia website yields no results.

Given these expectations, I insisted on a try-and-buy contract, which are not default in Switzerland (as opposed to the EU). My fears proved right, it wasn’t long until I encountered the first problems with nVidia’s crap: the network chip is unable to deal with segmentation offloading for larger packets, e.g. those with IPv6 payload in a bridging context, and generic segmentation offloading has to be turned off on the interface:

ethtool -K eth0 gso off

This fixes the issue, and so I stuffed it into /etc/network/interfaces and decided to keep the machine, especially after having invested the time into the server to figure out how to work the watchdog and the IPMI card. The folks behind Transtec’s support hotline are helpful, but it took me a bit of time to get the information I wanted out of them. At least they deemed it perfectly natural that I wanted to run Debian, and never questioned that.

Let’s document some of the more internal specs here for posterity:

The BIOS gives the impression of two separate watchdogs, one on the IPMI card (a SIMSO+) and one on the mainboard itself (a ?SuperMicro H8DMU+). Transtec told me that ?SuperMicro disabled the IPMI watchdog (called “BMC watchdog” in the BIOS) with firmware 1.29, leaving only the one on the motherboard. It took a bit of time to find out that this was a W83627THF and supported by the w83627hf_wdt driver, which I configured with module options timeout=120 nowayout=1. I left the BIOS setting at “disabled” since that would otherwise interfere with booting e.g. the awesome grml live system by rebooting the machine after the set amount of time.

It also took a bit of time to get SOL working with the IPMI card. In the end, I found it to work best by configuring the console redirection in the BIOS to use COM2 with 38400/n/8, using hardware flow control, redirection-after-POST always, and vt100 emulation — ANSI and vt-utf8 emulation were horrific. I instructed the bootloader to pass console=tty0 console=ttyS1,38400n8 to the kernel (order matters), and configured agetty in /etc/inittab like this:

T0:2345:respawn:/sbin/getty -8hL ttyS1 38400n8 vt100

To guard against the worst, I also left a grml CD in the drive, to be able to boot a rescue system via SOL in case everything else was broken. The following kernel boot parameters enable me to use the rescue system via IPMI:

vga=normal noeject noprompt console=tty0 console=ttyS1,38400n8 forensic

Michael Prokop of the grml project tried to create a customised ISO image with these options for me, but I kept getting medium errors trying to read it, independent of the burner, CD-writing-software, operating system used to burn, medium, and drive used to read, so it’s possible that the ISO image is faulty. Michael used the following command line to create it (supporting files are here):

grml-live -t ~/templates-madduck -c GRMLBASE,GRML_MEDIUM,AMD64 -o \
  /grml-live/grml64-medium_2008.11-madduck -a amd64 -s sid -v \
  2008.11-madduck -g grml64-medium -r Schluchtenscheisser -V -b

Until we figure out the problem with this, the grml64 0.2 CD in the drive will do.

The machine is now operational, but the IPv6 prefix I have still arrives at vera.madduck.net, a Xen-Instance hosted by Init Seven, which I will no longer need, once I find the time to migrate all the services it hosts.

NP: This Will Destroy You: Young Mountain

Posted Fri Nov 28 08:17:34 2008

Holger Levsen Interesting things to discover in Extremadura - or on the effects of Linex

Of course everybody in our crowd noticed the huge "Wifi zone powered by Debian" sticker with a Deban swirl at the restaurant door where we had dinner And the Debian wallpaper among the other images on the screensaver on the restaurants computer was probably also noticed by many. What really freaked me out though (in a very positive sense) was that the owner/someone (? I have no idea, I talked with him, but not about restaurant ownership...) wrote the billing programm himself. When shown the features it looked to me like a good one, with a simple and nice looking interface and appearantly feature complete to manage the restaurant (including creditcard interface etc.). The cashier computer was running Debian and the app is written in gambas2, which is a BASIC interpreter with build-in database abstraction layers and supporting gtk and QT. And he plans to release this as free software. Yay. Yay Yay Yay!

Me looks forward to this to happen and also to get the .svg of the sticker

Posted Thu Nov 27 19:36:43 2008

Andrew Donnellan NCSS Posted Thu Nov 27 06:50:08 2008

Holger Levsen awesome bts and snow

Right now, I'm a happy hacker: I just added a keybinding and shell oneliner consisting of four piped commands finally invoking the bts command to my awesome configuration. So now I can press Mod+F4 (anywhere, anytime) and then either enter a bug number or get a tab completion list of bugs I already looked at. Totally awesome. And I guess there is room for improvements once I have used /usr/bin/bts more

In related news I'm currently flying from Zürich (which made me think about snow...) to Madrid, in anticipation of the Debian QA/i18n/ftpteam meeting, which will start tomorrow evening with a bus drive to Caceres, the town where ?DebConf9 will be held in 2009. And somehow I didnt feel like going through my mails, I rather wanted to do some interesting new stuff. So I started to read the bts manpage...

To bring this post to and end, I share Gunnars feeling about all these snow blog posts, you insensitive colds! Last friday morning, Hamburg was among the first cities in Germany getting snow (the cold was coming from Greenland, thus from north west and Hamburg is pretty much north-north-west in Germany). Unfortunatly, the snow was almost gone in the city by friday noon, so when all these "got lots of snow" blog posts popped up on planet, I felt a bit like Gunnar...

Posted Wed Nov 26 02:01:33 2008

Joachim Breitner Linux Journal on the Neo FreeRunner

A fellow lodger of my student dormatory just popped in and gave me the December issue of Linux Journal as a gift from his trip to the US  (thanks for that!). When I skimmed the front page, I immediatelly noticed the line “Reviewed: ?OpenMoko’s Neo ?FreeRunner.” The four page article by Cory Wright contains some general notes on the ?FreeRunner, a list of things he doesn’t like and – to my surprise – installation instructions for Debian on the ?FreeRunner! It’s nice to see one’s work used in such public places. I especially liked the line “I must say, the Debian installers sure have improved a lot since the Potato days.” (Of course, the installer for the ?FreeRunner is mostly a dumb script that can not be compared to the great official debian-installer that you can use on a PC.)

Posted Tue Nov 25 18:57:00 2008

Olivier Berger (pro) We’re hiring a FLOSS developper to work on bugtrackers synchronisation

We’re hiring a software engineer, for 15 months, to work on bugtrackers synchronisation

(see full version of the offered job description here — et une version en français également : ici)

We’re looking for a software engineer to join our PFTCR team, in order to complement our R&D manpower on the HELIOS project. We’re responsible for a work package whose goal is to study and implement a system which would fit in the HELIOS platform, to ensure synchonisation between bug-trackers.

The workplace would be here in Evry (France, Paris area) for a duration of 15 months, under a french CDD contract (starting first quarter of 2009). The development done during the work on this project will be contributed back to FLOSS projects.

Strong know-how in software development as well as interest for research issues are expected from the candidates. Also, a good knowledge of the open source development tools, and of the dynamics of the libre software development communities is expected (distributions, packaging, QA). A practical experience of contribution on an open source project would be a plus (typically as Debian developper, for instance).. Technical english skills will be required (as well as notions of french, considering the french nature of the environment).

If you’re interested and available early 2009, I definitely want to hear from you.
See more details in full version of the offered job description.

Posted Tue Nov 25 15:25:33 2008

Andrew Williams The Commuters vs. East Midlands

For quite a while now, commuters on the heavily loaded Liverpool to Norwich service have suffered with cramped conditions and late trains. Personally, I’ve been travelling this service for nearly four years and seen the highs and lows.

Originally the service was handled by Central Trains, who at their best used to run a terrible service, many people complained and nothing happened. November 2007 gave new hope, Central Trains were finally pushed to the sidelines and a new franchise took over the running of this critical route for Liverpool-Manchester commuters. At first many rejoiced at the sight of four carriages and a return to the level of service we expect. Trains ran on time, fully formed, and working well. Six months later, it’s a different story. What we saw was a reduction in service back to the good old Central Trains days. The issue now is that this service is worse than Central Trains ever was; four carriages are the oddity of the service, not the norm.

So enter Train Sardine, a new website for the disgruntled commuters who have to put up with this service. This group aims to give one voice for the the route and hopefully give some marked improvement, only time will tell but if your interested in helping out then check out the website.

Posted Mon Nov 24 10:41:34 2008

Martin Albisetti Gmail now has themes!

I suddenly opened up gmail, and saw a new theme.
It turns out, you can now choose from over 30 themes!
Screenshot of my spam:

Theme options:

Posted Wed Nov 19 19:17:18 2008

Olivier Berger (pro) CAS client libs need love in Debian : several pending RFS

We have made some progress towards more CAS-ified applications installable in Debian, and now have several RFS pending :

• libauthcas-perl : Client library for CAS 2.0 / AuthCAS Perl module
• libcas-php : CAS client library for PHP / phpCAS PHP library

So if you’re a Debian Developer and wish to help improve CAS support in Debian, please sponsor these packages.

Posted Mon Nov 17 17:01:45 2008

Joachim Breitner My very first font

For a project of mine I needed the pictograms for man and woman (as also known from toilette doors), in two different sizes, once filled and once as an outline. I coud not find these as a ?LaTeX symbol nor as a defined unicode character, so I searched the internet. I found some material as vector graphics (EPS), which I was using first, imported into my ?LaTeX document as images. But it felt wrong to use images for something that’s a symbol in the text.

So I installed fontforge, the apparently usual tool for that, imported the EPS files and with surprisingly reasonable effort created a ?TrueType font with these nice eight glyphs:

Quite a while ago I wrote here how to use single glyphs from a ?TrueType font in ?LaTeX. Based on that I created the neccessary files to use these in ?LaTex with these commands, in the order of the picture: \Mansym, \mansym, \Womansym, \womansym, \Boysym, \boysym, \Girlsym, \girlsym.

Here are the files: ManPictograms.ttf T1ManPictograms.fd ManPictograms.tfm ManPictograms.enc ManPictograms.sty. If anyone feels like turning them into a more proper ?LaTeX font package, they are welcome.

Posted Thu Nov 13 00:25:44 2008

Andrew Donnellan Book Review: Ozonomics - Andrew Charlton Posted Sun Nov 9 10:01:00 2008

Evgeni Golov Pimp my Mutt Uh, yeah, I did it
I patched my mutt-patched

You may ask why I did it, and what I did, so here we go:
I use mutt(-patched) on my Etch box to read and write mail when I'm not in front of my regular box, where I use sylpheed.
My mail is stored on an IMAP server (courier, actually it's the same box you retrieve this website from), so I use mutt's imap support (don't tell me about offlineimap and stuff, I know them).
Having multiple folders on the IMAP server, you really want to use the sidebar patch for mutt, or you'll get crazy.

But here start my problems. The sidebar patch does not understand, that IMAP often uses a dot (.) instead of a slash (/) as a delimiter between the folders.
Thus the sidebar will look like this:

INBOX

INBOX.Sent

INBOX.Drafts

INBOX.foo

INBOX.bar

INBOX.bar.baz

INBOX.bar.baz.archive

...

Looks quite bad, especially when you have deep hierarchies. So I wrote the first patch, sidebar-dotted, which makes the sidebar look like this:

INBOX

 Sent

 Drafts

 foo

 bar

  baz

   archive

Better, huh? Oh, if you want to see this, you'll need to set sidebar_shortpath

But this is still not as good as I want it, because I get something like this:

foo

  baz

   archive

 bar

INBOX

 Drafts

 Sent

Wonder why? I have imap_check_subscribed enabled, so I don't have to list all the folders via mailboxes, but the server returns the subscribed folders unsorted and you see the result

Here I came up with the second patch, sidebar-sorted, enable it with set sidebar-sort and you get a nice folder listing as you (I) wanted.

You want the patches? Get them in my homedir.
Have fun with them, and forgive me, if mutt's fleas will eat up your mail Posted Thu Nov 6 21:11:58 2008

Olivier Berger (pro) Adding GForge bugtracker support in bts-link

Part of our work in the Helios project will be on bugtrackers synchronisation.

I happened to notice that bts-link’s maintainer called for help, which triggered more interest in that tool.

I’ve started working on bts-link to see how it works (cool, it’s Python and if it can be useful for Helios, and started implementing GForge tracker support in bts-link. That should help keep track of Debian bugs wrt upstream bugs for projects hosted in GForge forges (like Sympa, for instance, whose bugtracker is hosted in ?SourceSup).

You may find my git repo at http://www-public.it-sudparis.eu/~berger_o/git/bts-link.git which hopefull contains my proposed changes (I’m new to git, so I hope I did everything right…).

Posted Mon Nov 3 10:51:29 2008

Martin F. Krafft Visual SSH fingerprints

Recently, people have picked up on OpenSSH’s new “feature”: visual SSH fingerprints.

It hurts to see this “feature” in a software like OpenSSH, which is so integral to everything we do, because it’s a waste. It’s additional code, and thus an additional risk of bugs, and it has a net security benefit of zero, NULL, zilch, nada, nothing, nix, nadje, oomph!

The theory is that you learn to recognise the general shape of the visual fingerprints of your hosts, which is easier for us to remember than strings of hexadecimal numbers. So, for instance, if you ssh to pony.debian.net, you get to see something that’s not entirely unlike a pony:

Host key fingerprint is 45:2f:a5:d8:13:95:ba:03:51:c4:8d:ac:82:a8:4c:6a
+--[ RSA 2048]----+
|         ==+o.   |
|        .++=o    |
|   . .  .o*..    |
| .. . . o..o     |
|+.     .S. .     |
|oE        o      |
|.          .     |
|                 |
|                 |
+-----------------+

Rejoice! Because now, should pony.debian.net ever present a new SSH fingerprint, when OpenSSH screams at you:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.

then you can look at the picture and say: “yeah, I knew that”, because your pony has suddenly transformed into the visual representation of a giant fart.

On the other hand, the new “feature” makes day-to-day interactions a lot easier. Imagine you need to ssh into a new host. You take a piece of paper and call up the admin to ask for the fingerprint, but instead of a series of hexadecimal digits, he says “it looks like the easter bunny and a bit like southern Italy”.

Great “feature”. Thanks. I would appreciate if this sort of crap stayed out of important software. Dan Kaminsky might have some good ideas, but most of the time he’s on crack. Get a grip. Stop being a fanboy.

NP: Kinski: Alpine Static

Posted Fri Oct 31 08:01:07 2008

Francois-Denis Gonthier Annoying non-breakable spaces in Bash/Zsh Posted Mon Oct 27 18:39:23 2008

Raphaël Hertzog Debian membership reform

Following Ganneff’s post to debian-devel-announce, several discussions have again started on the topic of Debian’s membership and several proposals have been made. Unfortunately none of these proposals try to resolve the underlying trust problem that has been growing over the years. Despite the NM process (or maybe due to it), we managed to give DD status to people who are motivated but whose technical skills are doubtful (at that point people ask for an example, and as much as I hate fingerpointing, here’s an example with #499201. The same maintainer created troubles with libpng during the etch release cycle and tried to take over a base package like mawk recently).

With our current model, all DD can sponsor, NMU, introduce/adopt/hijack packages without review. This is fine as long as we trust the body of DD to contain only skilled and reasonable people. I believe that premise to be somewhat broken since Debian has become too big for people to know everybody and since the NM process had no way to grant partial rights to volunteers who were motivated but that clearly had not shown their ability to handle more complex stuff than what they had packaged during their NM period (like some trivial perl modules for example).

Thus I strongly believe that any membership reform must provide a convincing answer to that trust problem before being implemented. I took several hours to draft a proposal last Friday and I’ve been somewhat disappointed that nobody commented on it. I hope to draw some attention on it with this blog post.

The proposal builds on the idea that we should not have “classes” of contributors but simply two: a short-term contributor and a long-term contributor (those are called Debian Developers and have the right to vote). But all contributors can be granted “privileges” as they need them for their work and each privilege requires the contributor to fulfill some conditions. The set of privileges and the conditions associated all need discussions (but I have personal opinions here, see below). There’s however one privilege that is somewhat particular: it’s the right to grant privileges to other contributors. Handling it as a privilege like another is on purpose: it makes it clear that anyone can try to get that privilege and the procedure is clear. In practice, imagine that set of people as a big team encompassing the responsibilities split over DAM/AM/FD/DM-team and where all members can do all the steps required to grant/retire a privilege provided that 2 or 3 members agrees and that nobody opposes (in case of opposition a specific procedure is probably needed). I called that set of people the Debian Community Managers. It should contain only skilled and dedicated developers.

One of their main duties would be to retain the trust that the project as a whole must have in all its members. They would have the powers to retire privileges if they discover someone that has not acted according to the (high) expectations of the project.

Among the privileges would be “limited upload rights” (like DM have currently), “full upload rights” (like DD have currently although it might be that we want to split that privilege further in right to sponsor, right to package new software, right to maintain a package of priority > standard, etc.) and “developer status” (email + right to vote, once you can prove 6 months of contribution).

There’s lots of stuff to discuss in such a proposal (like how to decide who gets what privileges among existing DD) but I think it’s a good basis and need some serious consideration by all the project members. The NM process is there only so that we can collectively trust that new members are as good as we expect them to be and trust can only be built over time so it’s good that we can grant privileges progressively.

Some people believe that I’m reinventing a new NM process that will end up to be very similar to the current one. My answer is that the conditions associated to each privilege should be based on the work done by the contributor and the advocations that he managed to collect. It should not be a questionnaire like “Task and Skills”. This, together with the distribution of the power/work on many people, would render this system very different from today’s NM process.

Some people believe that I’m copying Ubuntu when designing this since it’s somewhat similar to the process to become MOTU and/or get upload right to Ubuntu’s main component. Let me say that I’m not copying deliberately at least, I simply took the problem from the most important side. But remember that many aspects of Ubuntu have been designed by Debian developers that tried to avoid known pitfalls of Debian, and maybe they got some things right (or better at least) while doing this.

Partagez cet article / Share This Posted Mon Oct 27 12:56:56 2008