DevOnLinux

ShellEd is an interesting plugin that provides some features to who wants to write bash scripts using Eclipse.

The main feature ShellEd provides are

• syntax highlighting
• autocompletition
• integration of man pages

I’ve encountered some problems while trying to install it because it has some dependencies and since everytime i’ve installed it i fell into errors i decided to write this quick post as a reminder. By the way, I am using Eclipse 3.5.2.

First of all, right now there isn’t any Update Sites that provides an easy and automatic installation of the plugin, so the easiest thing you can do is to download the plugin and add it as a local archive.

If then you try to install it, Eclipse tells you that ShellEd needs some dependencies that are not satisfied.

In particular it says that a org.eclipse.dltk.ui is not found. To solve this you have to install DLTK core library.

Right now there are two different version of DLTK: dltk 1.0 and dltk 2.0 and if you have some other plugin installed (such as PHP developer tool) you can have it installed using version 1.0

At the moment the last release of ShellEd is 2.0.0 M3 that only works with DLTK 2.0 so if you have DLTK already installed and you can’t update it you have to download ShellEd 2.0.0 M2.

To have ShellEd up and running you have to satisfy another dependency which is the Man library that comes with LinuxTools (nda another Eclipse plugin.)

As said here by Jeremy Allison, creator of SAMBA, also the mandrill of Devonlinux say no to Mono.

Software patents problem.

But the problem is that Mono is dangerous for Free Software. The heart of the matter is, as usual, software patents. Microsoft have patents on the technology inside .NET, and since the Tom Tom lawsuit, Microsoft have shown they are not averse to attacking Free Software using patent infringement claims.

Novell agreement with microsoft.

Miguel’s employer, Novell, has a patent agreement with Microsoft that exempts Mono users from Microsoft patent aggression, so long as you get Mono from Novell. Miguel takes pains to point this out. This is not a level playing field, or software freedom for all. This is a preferred supplier trying to pretend there is no problem. Sure there isn’t a problem, for them.

And all others?

It is vitally important to the continued success of the community development model that one part of the community does not enter into an agreement which gives some people patent protection while leaving other people out in the cold. That is why I was so opposed to the patent agreements recently entered into by Novell, Xandros and other companies.

This one is reported by Andrew Tridgell, negotiator with Microsoft for Samba.

Update 26-12-2009
Other valid reasons to say no to mono, moonlight, microsoft and the traitor de icaza.

developer Tom “spot” Callaway, Engineering Manager and Red Hat legal expert at Fedora, made it clear that the Fedora project, sponsored largely by Red Hat, will continue to leave the software out. One of the reasons was that the new promise does not protect Linux distributors any more than the old one did.

Just a quick post about tesseract, a quite good solution for OCR under GNU/Linux (specifically Ubuntu Karmic Koala).
First install it trough apt-get
sudo apt-get tesseract-ocr
Install also your preferred language (in my case eng -> tesseract-ocr-eng and ita -> tesseract-ocr-ita).

Ok, we are ready to do some text recognition…
But, under Karmic Koala, there is a problem with tif image as reported by myself here: https://bugs.launchpad.net/ubuntu/+source/tesseract/+bug/461177
The problem is due to a transparent alpha layer that some tif images have (investigation needed here…*), so before do text recognition is necessary to eliminate it, elsewhere tesseract will generate an empty file…
Just install imagemagick and from a shell do this steps:
convert inputimage.tif inputimage_tmp.pbm
convert inputimage_tmp.pbm inputimage_ok.tif
Original solution founded here.

Now we are finally ready to launch tesseract on our tif image.
Just do
tesseract inputimage_ok.tif outputfile
and tesseract will generate outputfile.txt with recognized text.

ps. The packaged version under karmic is 2.03 and not the last one, 2.04, that, as advised on this page, fixed it. So if you prefer, remove old version and install the new version from source.

* Solved. In Gimp is possible to remove the alpha layer. Just go to
Layer (Livello) -> Transparency (Trasparenza) -> Remove alpha layer (Rimuovi canale alpha)

Great article by Colin Guthrie, a Pulseaudio hacker (read it as developer), about the actual state of sound stack in GNU/Linux.

Many improvements are done to ALSA and now the code is better and cleaned in the kernel driver while the userspace library it’s rather complex, for backward compatibility. Pulseaudio, the sound server, go forward, and manage some new requirements of an actual multi-user, multi-source desktop environment, like, quote Colin:

• Software mixing
• Independent (per-application) volume control
• Dealing with permissions (is the user allowed to access the sound device?)
• Dealing with Bluetooth devices
• Dealing with Network based devices (UPnP, Apple Airtunes, Native PulseAudio etc).
• Handling the moving of streams between outputs.
• Handling sound from remote applications run via X11 over a network.
• Dealing with routing policy (Music goes to USB speakers, Desktop sound events to built in speakers, VoIP to Bluetooth headset)
• Effects to promote HCI (e.g. positional event sounds  – button clicks etc, coming out louder on the left hand speaker when triggered from the left hand side of the desktop)
• Power Consumption and Efficient savings.
• Reduces risk of buffer under-runs.

So, GNU/Linux users stay calm and contribute everyone in your manner to the FLOSS world.
Also the sound stack is an a good state

I have recently discovered Evolution Mirror, an interesting Thunderbird add-on that aims to mirror Thunderbird calendars to Evolution Data Server. This lets me to manage my calendars with Thunderbird as usual and to see my events in the Gnome Clock applet.

It is still in development but it is a great intitiative of Teester because it’s a good way to integrate Thunderbird with Gnome.

The plugin is written in Python, and it needs the python-evolution binding. Now i will explain you how to install it. I am using Ubuntu 8.10 Intrepid Ibex 64 bit version.

Obviously you need on your system Thunderbird and its calendar extension: Lightning.

Open Synaptic and install these packages and their dependencies:

python2.5-dev, python-gtk2-dev, libecal1.2-dev,
libgdk-pixbuf-dev, libebook1.2-dev

or using a terminal:

sudo apt-get install python2.5-dev python-gtk2-dev libecal1.2-dev \
libgdk-pixbuf-dev libebook1.2-dev

Download the evolution-python binding from Conduit site.

Open a terminal and digit:

tar zxvf evolution-python-0.0.4
cd evolution-python-0.0.4
./configure
make
sudo make install

Well done, now evolution-python bindings are installed. Now download Evolution Mirror add-on and add it to your Thunderbird Add-ons.

Open Evolution, create an account. You have to do this because it creates some basic data such as the Personal calendar.

Now open your Thunderbird and start add Tasks or Events and you’ll see them on the Gnome Clock applet.

As i have already said, the plugin is still in development, for now it does not add events and tasks that has been already inserted before. It also merge all calendars’ data in one unique Evolution calendar. These are some missing but i think and hope that they will be fixed soon.

Anyway is a great work! I hope to have time to help the developer in this add-on, also because it will be very useful with my still-in-development tool called SyncIt. Take a look on my Trac to know something about it even if it is not updated and poorly documented.

Today i’ve decided to add to my Eclipse IDE the Mylyn plugin, an add-on that lets manage bugs and planning of a project inside the IDE itself. Mylyn can be used with a lot of bug tracking tools and since i use Trac i’ve decided to link them together inside Eclipse.

I assume you have installed Trac on your local server, or on your Dreamhost account. To enable communication between Trac and Mylyn we have to install and enable the XmlRpcPlugin that you can download from trac-hacks.

After the download, copy your plugin on the system where Trac is installed. Uncompress the archive and go to the 0.10 folder if you have Trac 0.10 or trunk folder otherwise.

Now digit these commands:

chmod 755 -R *
python setup.py bdist_egg

Wait until the Python egg is created and then copy it into the plugins directory of your Trac environment. The egg file is in the dist directory created during the egg building.

Now go into your Admin account of your Trac web interface and go to Plugins page. You’ll see a TracXMLRPC 0.1 field. Clicking on it you’ll see some component. You have to enable these components as shown in the next figure.

Well we’ve almost done. Now we have to install Mylyn and Mylyn extras into Eclipse.

Start Eclipse and click on Help -> Software Updates. Click on the Availabe Software tab. Click on Add Site button and paste these two “repository”:

http://download.eclipse.org/tools/mylyn/update/e3.4

http://download.eclipse.org/tools/mylyn/update/extras

Now select to install these features:

Wait until Eclipse asks you to restart to update changes and then you’ll be able to use Mylyn with your Trac environment.

Directly from MIT, Seek, simple faceted browsing of your mailbox.
This plugin is released for Mozilla Thunderbird.

There is also a good screencast: watch, download the plugin, install, love it…

Open Source Innovation, of course!