Between Linux and Anime

So after a good long time not being able to play this Facebook game we’re building for P2P-related research, which runs on Java Web Start, I finally got pissed today and sat down and finally got to the bottom of it.

Because Java isn’t free technology and all that, OpenSUSE actually comes preinstalled with OpenJDK instead of the common version of Java distributed by Sun. With this default configuration, Web Start (JNLP) files on the internet will open by default in an open implementation of Java Web Start called ‘IcedTea Web Start’, which I hear works reasonably well – but outright doesn’t work for some cases, like mine.

For people who, like me, need to run Sun’s version of Web Start from Firefox – first, you need to grab and install Sun’s version of the Java runtime using your software package manager (in OpenSUSE the package is called java-1_6_0-sun). Verify that you have a program called ‘javaws’ after this step. You can simply type ‘javaws’ into an open terminal and make sure it is recognized as Java(TM) Web Start.

Okay, next all we need to do is get Firefox to use javaws when opening JNLP files. For other distros you’d go to Edit > Preferences > Applications in Firefox, look for JNLP, and change the setting so it uses javaws. On OpenSUSE, Firefox is integrated so it takes its file-association settings directly from KDE. So you’ll have to instead go to KDE’s systemsettings (Configure Desktop) > Advanced Tab > File Associations. Here, run a search for JNLP, then add ‘/usr/bin/javaws’ to the top of the Application Preference Order.

We’re done! Next time you open a JNLP Web Start file in Firefox, it should offer to use Sun’s Java Web Start to open it :)

Damn, I’ve got so many things I should have written and posted but Chinese New Year stuff keeps getting in the way and unexpected problems keep cropping up. I just solved the latest one (unexpected problem), and I think this solution needs to be posted, so bear with me :)

If recordmydesktop gives you ridiculously slow frame-rate in it’s output video, you may be a victim of the “libtheora above v1.1.0” problem. Try the following for a quick-fix:

Add --v_bitrate 2000000 to the options you pass to recordmydesktop. If you use a frontend (like gtk-recordmydesktop or qt-recordmydesktop), look in your configuration for an “Extra Options” section and paste --v_bitrate 2000000 into it.

Worked like a charm for me. Source.

FileZilla and other such applications that deal with remote file transfer protocols have all become deprecated on my desktop when I discovered that you could directly browse those files using dolphin and directly edit those files with kwrite/kate, thanks to Kio. (You could do it on Gnome too, for example to browse an ftp location, just type “ftp://your_ftp_host/path” into the location bar on nautilus, dolphin, or konqueror). I’ve been using the fish Kio-slave to browse ssh-secured locations for some time now, but today I needed to access a location secured by ssh key instead of a password. It was not immediately obvious to me how to do this, so I’m gonna quickly pen down my solution.

When you point dolphin to an ssh-secured location (type “fish://your_host/path”), it will attempt to connect and prompt you for a password. There is no way to tell it at this point to use an ssh key file instead to the best of my knowledge. What we’ll need to do is to modify the ssh configurations to look for your ssh key file when authenticating. Simply add a line like the following (or uncomment / copy and modify it, if your config file already has such a line):

IdentityFile path/to/your/key/file

The system-wide config file is typically found at /etc/ssh/ssh_config, and the per-user one at ~/.ssh/config. The latter may not exist by default, you could simply create it as a copy of the system-wide one. With this done, you should be able to connect with fish with no problems.

I have not tried this out on Gnome, but I suspect things are not far different there.

Just a quick note-down. I was mildly surprised to find that the modern Linux environments I use (that’s Ubuntu and OpenSUSE) do not gracefully support MIDI as they do stuff like MP3 and WAV. Too old a file format? Hmmm, come to think of it, I’ve been on Linux for more than two years now and this is the first time I have ever tried to listen to a MIDI file. Oh well.

The answer is Timidity. I won’t claim it is the best answer – I was lazy and wasn’t up to doing detailed research, so I just installed a bunch of programs off the repository that look like they might do the job, and tried them one by one. Disappointingly, most of them wouldn’t work out the box despite promising descriptions. So as it turns out, the first program that Just Worked ™ was Timidity. So here I am telling you about it to save you time ;) You’ll need to install it off the repo in Ubuntu, while OpenSUSE appears to have it installed by default.

To play a MIDI file, simply do

timidity [yourfile.midi]

Command-line haters can get a nice gtk-based GUI too by installing the extras packages for Timidity and doing:

timidity -ig

I know a complete solution should also make it so that click/double-clicking on a MIDI file automatically opens the appropriate player, but I’m too lazy to check for something that gets all that done on installation, especially since I only wanted to play one MIDI file. Just manually configure your system to call timidity or something.