I finally got the time to get something I’ve been thinking about for a while down on paper (but not real paper of course), and my article discussing using undo on the desktop to reduce the annoyance of modal dialogs has been published in GeekDeck Issue 3, which was released today. Hope you enjoy it! Here’s a list of all the articles in this issue:

• Editor’s Letter
• Og looks at Foresight Linux
• Damien interviews OpenCandy CEO
• Why does society hate geeks?
• Are modal dialogs a thing of the past?
• Our feature on creating a Live CD
• Mark gets angry…Very angry
• Pete get’s something off his chest
• Is the Internet really so virtual anymore?
• The best bag in the business?
• Pete gets a break as Mark talks E3

laszlo@sescento:~$ sudo mount /dev/dvd1 /media/cdrom
mount: block device /dev/sr1 is write-protected, mounting read-only
mount: wrong fs type, bad option, bad superblock on /dev/sr1,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

Looking at the system log, shows the following message:

laszlo@sescento:~$ dmesg | tail
...
[588493.006569] UDF-fs: Filesystem marked read-only because writing to pseudooverwrite partition is not implemented.
[588493.214121] UDF-fs: No fileset found

After googling this problem for a while I found many Hardy users having this problem, and links to solutions which involve patching the filesystem driver and recompiling the kernel module. However I am running Jaunty, which was released just last month. It should have the latest driver necessary to read the new UDF format produced by Roxio.

After finding many Ubuntu Forums threads which were no help, I found a comment on this UDF format bug which apparently has been fixed in Intrepid. The comment mentions to make use of the “session” and “lastblock” mount options.

As the comment suggested, I tried running dvd+rw-mediainfo and getting the lastblock value of 1678800. The following command gave the same error message.

sudo mount /dev/scd1 /media/cdrom1 -t udf -o ro,user,noauto,exec,umask=0,session=0,lastblock=1678800

After playing around with this command for a while I figured out that 1678800 is one of the only values that doesn’t work. Specifying 0 or 1678800 or 1678801 causes the mount to fail. Specifying almost any other number allow the disc to be mounted and read. I can speculate that if the lastblock value seems valid, for example it is close to the end of the track it tries to use it. However with a value that is almost certainly wrong, it tries to search for the proper value. To me it still does not make sense why if the lastblock option is not specified, the disc cannot be mounted.

So for simplicity I will just use the value 1. Here is the command which allowed me to mount the disc successfully:

sudo mount /dev/scd1 /media/cdrom1 -t udf -o ro,user,noauto,exec,umask=0,session=0,lastblock=1

Now its time to listen to the music and watch the movies contained inside.

Carleton University’s Health Services and the university’s Administration continue to monitor the situation regarding Human Swine Influenza.

I did not realize we had human swine at our univeristy. Did a DNA splicing experiment in the biology department get out of hand? It’s good that health services is concerned for the well being of everyone including hybrid beings.

But as Håkon Wium Lie, the CTO of Opera once said:

…I’m no fan of either specification. Both are basically memory dumps with angle brackets around them.

He was talking specifically about the document formats competing for standarization at the time. More generally, he was talking about the whole idea of XML file formats. I remember thinking about Jokosher’s own file format after hearing this quote. It is an XML based format that I largely designed myself.

I will admit that our format is in a lot of ways a memory dump with angle brackes. The main nodes <Project>,<Instrument> and <Event> have the same name and structure as the classes that implement them. Each of these nodes also has a subnode called <Parameters> which is simply a list of the variable name, type and value of all the class variables. This only works well for simple data types; for list and dictionaries we have more complex structures.

In previous versions of Jokosher, I needed a easy way to store the very large list of volume levels used to draw the waveform. I figured that putting each number in its own XML node would take a lot longer to parse and consume much more memory than necessary so I created one simple node that looked like this:

<Levels value="0.911560058594,0.913299560547"/>


Imagine the above except with three thousand floating point levels, as is required for a typical five minute song. At this point it starts to get messy and stops looking like proper XML. It is also harder to decipher, and much more like a memory dump. Luckily the current version of Jokosher does not use this anymore. I stores the level data in a separate file that is just a raw dump of the bytes from the array.

Even though I have just shown Jokosher’s file format to be essentially a memory dump with angle brackets, I don’t feel bad about it. It makes our job as programmers easier, and the whole program is still simple enough that you can figure out most parts of the file format without documentation.

Today I had the chance to look at the file format used by Apple’s GarageBand, a program with a very similar purpose to Jokosher. It was interesting to find that like Jokosher, GarageBand has a folder for the project which contains the project file as well as a separate folder for all the audio files. Also just like Jokosher the project file is XML based.

After a few <dict> nodes obviously representing a dictionary data structure, there is a <data> node containing (wait for it…) 2584 lines of base-64 encoded data, and the entire XML file is only 2794 lines! Talk about a memoy dump with angle brackets. And you though your file format was difficult to interoperate with! If you really want to peer at the impurity, you can download the entire file.

Since we removed our ALSA specific code, we now use the GstPropertyProbe interface on the “device” property to retrieve the list of devices. Currently this only works with ALSA, but if you are using Gstreamer from CVS the patches of mine that were recently committed make it work with PulseAudio as well. JACK does not support the “device” property at all, since the JACK control panel is used to select devices.

As an added bonus, removing the ALSA specific code will make it substantially easier to make Jokosher work on Windows. None of our developers are doing a Windows port,  but if you are interested you are certainly welcome to try it out and see if it works.

This code is not yet merged into the main branch, but you can get it from the custom-audio-src branch in Launchpad and give JACK a try.

It feels great.

Eventually we decided that we are a Gnome application, but so far we have yet to add any hard dependencies. I have wanted to integrate Gconf for a while now, but I never find the time. Even though we don’t have the Gconf or GnomeVFS (now GIO) dependencies, we always felt as if we were part of the Gnome community. I mean our mailing list is at gnome.org.

I am a little late on this one, but everyone is talking about the awesomeness that is the Linux Hater’s blog.  Last month the Linux Hater wrote a very nice article about how to write a Gnome application. This was a follow up to the very popular article: How to write a KDE application. Since I have never written a KDE application, I have no comment there. But I would like to see if Jokosher followed all the steps, so here’s my analysis:

Find some reasonable app from another platform (Windows, Mac, KDE, whatever, but preferably, Mac). Bonus points if there are already 3 other gtk-based alternatives who don’t want to integrate with Gnome.

We don’t really like to compare Jokosher to Apple’s Garage Band, but it does make it easier to explain the concept to people so I guess we are guilty of that. But I am glad to say the reason we started Jokosher is because there is no GTK+ multi-track audio editor (single track audio editors are totally different and don’t count).

You MUST have a g somewhere in the gname. Extra credit if you can make it a “gn”. If you can use “gnu” or “gno” or “gna” you’re are gnawesome, and your app is already worth using. Make sure the name of your app bears no relevance to what it actually does. Also, NEVER document if the g is pronounced with the hard-g sound.

People have told us that Jokosher is a ridiculously stupid sounding name, and yes it does not have any relevance to what the program does, but still there is no g.

Use at least two object frameworks. Three is even better. I mean the “O” in Gnome stands for object, after all. Take your pick from Corba/Orbit/Bonobo/D-bus. Make sure at least one of them works over the network, but make sure your app never actually uses it over the network.

Nope sorry. I really want to give Jokosher a DBus API, but I haven’t got around to it.

Remind yourself that OO in C is not so bad. assert(gtk_no_really_its_not_so_bad). Also, remind yourself that GTK+ is way better than Qt because it has no commercial company writing code for it. So, you know, it’s more free, or something, and it’s got a + in the name.

Phew, we escaped this one. We don’t have to use C because the entire program is written in Python. And we don’t use Qt because at least at the time PyQt and PyKDE were poorly maintained and lacked any community or documentation.

Generate wrappers for every conceivable language, but make sure none of them work exactly how you want. Inisist that your distros package each wrapper in a separate package.

Since we decided to write Jokosher in Python, we weren’t intending to write bindings for any other languages – especially C. This is more of a library thing anyway, not a desktop application thing.

Explain to at least three other programmers how glib doesn’t really have much to do with gnome. Because they care.

What is glib? All the types and data structures I use are the Python ones.

Don’t forget a Tango Icon!

This one is dead on. We had Tango icons before we had audio support, and we’re an audio application! But there’s no way you can argue this is a bad thing. Tango is great.

Make sure your app builds on windows, but looks like ASS.

We’ve been meaning to try this, but we have some ALSA specific code right now and no one wants to take on the challenge of compiling Gstreamer on Windows. I disagree with the ass part. If there’s one thing Jokosher does well it is look good!

Enumerate all the features you want your app to have.

Cut 90% of them. Because they’re hard to do. But tell everyone that they don’t actually need that feature.

Implement 2% of them. Hide the other 8% in gconf. Hide them well.

There are a lot of features we would like to do, but are very difficult both from an implementation perspective and a usability perspective. But given enough time we will get to them as long as we can find away to do it without crowding the interface. Despite what the Linux Hater says, it is sometimes better to leave a feature out than wreck the interface with it. Also I have been meaning to hide features in Gconf, but like I said I never got around to it.

Your interface must not have more than 4 buttons.

Each instrument in Jokosher has at least four button on it. Plus three more that appear in the selection context. Despite all the yelling there is a balance there between too many and too few buttons.

Make sure it depends on at least four other libraries with g’s in their name. That raises your apps’ gnomyness

Gstreamer, GObject (doesn’t really count cause its part of GTK+), Glade. That’s only two. Three if you count Gnonlin.

Don’t use Mono, because you are spreading your STD’s to everyone. No, wait, use Mono, because it will make you way insanely more productive. Wait, no, don’t use Mono, because if you do, some freetard distro that nobody uses won’t distribute your app.

No Mono, got it.

Depend on a module that is “heading toward planned deprecation” so that it will now be “at the end of the Obama presidency we will almost have consensus of heading toward a planned deprecation over 20 years.”

I don’t think we’ve ever done this. We started using Tango icons and Cairo graphics pretty early on so I think we are far enough past deprecation.

Ressure yourself that even if your app sucks, at least it follows the HIG.

Wow. What a perfect one to end with. I don’t think you could sum up Jokosher in a more controversial way than that. It’s true Jokosher sucks at what it is supposed to be good at, namely recording and mixing. Yes most of these are problems with Gstreamer that we haven’t managed to fix yet. And yes it sometimes doesn’t like your hardware and sends crazy opaque error messages. But many people have told us how much they like the interface, and we love giving it a lot of attention and polishing it up. We follow the HIG almost religiously. 100% guilty here. Damn.

Four or five out of fourteen depending on how you count it. Either way that’s a fail. So according to the Linux Hater, Jokosher is not a Gnome application. Let’s assume that’s a good thing.

I dread moving my internet because the last time I moved into a new house I was originally planning on getting a Rogers high speed cable, but the guy who was supposed to install it never showed up. It turned out they called me the next week to confirm my appointment — they had scheduled it a week to late. But by that time I had already booked an appointment for another ISP called 3Web to install the almost identical cable high speed internet.

Finally after 21 days, my internet connection was active and I could get back to IRC, MSN and all surfing when I am bored. I lived in that house for two years and I kept 3Web service the entire time. The connection went out for about a day one time, but otherwise I had no problems with it. It was decent, but it wasn’t spectacular or impressive. Nothing to blog about.

Now two weeks before I moved, I called 3Web to let them know. They asked me what day I would like the service at the new house to be working. I said the first of May and they said okay. I thought, “That was too easy”. But on the day I moved, by the time I had a chance to open up the laptop and try it out, it was already working.

Contast this wonderful example of flawless service with my phone line. Bell recommends that you use the moving form on their site. So I did. However I got no response, no call to confirm from them or anything. When I got to my new house, the phone line was dead and I was still paying for the phone at my old house. As punishment I have decided I will no longer have a home phone. Right now I’m doing perfectly fine using Skype for outbound calls, but I still haven’t found a good provider of incoming VoIP lines for a 613 Ottawa number. I would be nice if SkypeIn was available in Canada. Maybe in the future I will get a cellphone, but it won’t be one from Bell.

There are certain companies which have such terrible service you dread dealing with them, and try anything to avoid it. Unfortunetly in Canada many of the monopolies are these kinds of companies, and these monopolies are so pervasive that everyone forgets what good service is like, or at least assumed there was no possible business model that would allow good support and cheap prices at the same company. My experience with 3Web, and flying with WestJet reminded me that is possible, so now I am voting with my wallet.

At work we have a corporate firewall which only allows outgoing traffic on HTTP port 80. This is okay because MSN has an HTTP method, which allows you to connect from anywhere. Recently the HTTP method stopped working with Pidgin. You could connect and see all your friends that are online, but if you tried to send a message it would report a connection error. A lot of people use Pidgin, but not all of those people use MSN with Pidgin, and out of those people most use the non-HTTP method, so they are fine too. But for the rest of us, this sucks. You can’t talk to anyone, and apparently a lot of people were very affected by this as you can see in the Pidgin bug tracker, and on the Ubuntu Forums.

This morning I was finally fed up. So I spent a few hours researching the MSN protocol, reading the Pidgin source code and capturing packets from the official Microsoft Windows Live Messenger client using Wireshark. After about four hours of insanely fun network reverse engineering, I had a fix.

I thought this as gonna be difficult, I would have to learn all the Pidgin code, and it might take days to figure out the newest changes in the proprietary MSN protocol. But it only took a few hours. Usually I would just sit back and wait for the Pidgin developers to fix it, because it’s their domain. Luckily this time I didn’t. I took a shot and it paid off big time!

I encourage all of you to dive head first into something you know nothing about and see if you can make a difference (especially those people who keep asking me about Jokosher bugs ). That’s what free software is all about.

It is nice to finally have a server to put my own programs on and have it accessible from anywhere through my domain name. I originally thought that I would be using Python for all my web stuff, but do far I have found PHP to be really simple to use. This is mostly because in Python you have to put all your HTML in doc-strings, which prevents you from having syntax highlighting, and breaking up the string when you need to insert a variable is not elegant. I find PHP method of allowing you to jump in and out of HTML mode to be a much nicer solution.

Right now I’m only playing with Wordpress and few PHP web apps that I wrote myself. Maybe one day I’ll get around to trying out Django and all that jazz, but currently I like 99% of what Wordpress does and I therefore only have to spent time tweaking the remaining 1%.

Speaking of time, because of work and generally being lazy, I haven’t put a lot towards Jokosher lately. Summer is almost over and I will soon be revving everyone to get ready for our unit testing and our beta releases in the fall. Otherwise everything is gonna slip past Christmas. Let us hope it doesn’t come to that.