Category: Linux

Linux is my primary operating system. I used it on the servers, desktops, laptops, netbooks, and even mobile phones since approximately 1997. I’ve tried a number of distributions over the years, and even created a couple myself. I still look around sometimes to see what others are up to. But most of my machines are running some sort of Red Hat – either a quick and easy Fedora Linux, or a stable and secure Red Hat Enterprise Server, or a cheaper CentOS alternative.

And while by now I am very comfortable in the Linux environment (both graphical and command line), I still discover a lot of new and interesting things about it. When I come across something worthy, I usually share it with the rest of the Open Software world, using this category.

Fedora 12

I’ve upgraded my laptop to Fedora 12. I know, that wasn’t the smartest move, since the conference which I am attending is not over yet. But I just couldn’t wait.

The upgrade process was as simple as:

Open up the terminal, switch to root user, and run “preupgrade“.
Select Fedora 12 from the list of available options and click Next.
Watch the downloads in progress. Or, as I did, go and have a few beers and socialize.
When you are back from the beers, before you crash into bed, click the Next button for the installation to start.
Go to sleep.
Wake up to a shiny Fedora 12 distribution on your computer.

The only thing that got me worried for a second was that after the laptop rebooted into Fedora 12, for some reason the resolution of the screen went down to 800×600 or something like that. But all I had to do was login into Gnome, navigate to System / Administration / Display and switch resolution back to what it was before the upgrade.

I didn’t have much time to explore things yet, just read through release notes and features list. However things do look to be faster and more polished. I’ll have to use it for a few days to know for sure.

Cyprus Linux User Group meeting

As you might have heard, there was yet another Cyprus Linux User Group meeting yesterday. It was, as usual, aligned to the recent Ubuntu and upcoming Fedora releases. This time the even took place in the new University of Cyprus campus, in Nicosia. There were slightly more people than the last time, but I was hoping for even more.

There were three presentations and one workshop. Theo did a traditional Ubuntu Linux presentation in Greek. Alexandros presented, also in Greek, about Linux in Cyprus education – a very interesting one, too bad my Greek is so poor. And then I did a presentation in English about what Linux has to offer to students and why they should get involved. Here are the slides from my talk (Linux for Students and Linux for Students). After the presentations, Constantinos did a workshop about Compiz and Elisa media library. Both looked quite impressive.

After the event a few of us went to the tavern for some really awesome meze and beer. Altogether – good fun.

P.S.: If you missed the event, keep an eye on Ubuntu Cyprus web site and forums for announcements of the next one. Hope to see you there.

Running simultaneous Firefox sessions with different profiles

The more and more I use Firefox, the more add-ons I install, and the heavier it becomes. Recently I got to the point where I am annoyed by all the heavy weight functionality, but cannot remove it complete because I need it occasionally.

The solution to my problem turned out to be pretty simple, even if it required some Google searching and IRC chatting – multiple profiles.

By default, when you run Firefox for the first time, it created a default profile to store all your stuff – saved passwords, bookmarks, add-ons, etc. However it is possible to create more profiles and separate things a bit. For example, I currently have three profiles:

Browser. I use this one for generic browsing stuff, such news reading, email, etc. Firefox add-ons for Gmail, Google Calendar, YouTube, Flickr, and other major sites I used frequently are installed under this profile.
WebDev. I use this one for my web development needs. Web Developer, Firebug, Live HTTP Headers, and any other add-ons that help me do my job are installed under this profile.
Default. I keep this one clean and empty. Sometimes I want to see how site behaves in the browser with default settings – for this I use the Default profile.

Creating this profiles in very easy. As per Firefox documentation, all you need to do is close all current Firefox windows, and then run Firefox from command line with -ProfileManager parameter. A small window will popup that will give you options to create, rename, and delete profiles, as well as select with which profile to start the new session.

The problem that I came across was running several Firefox sessions in parallel, each with its own profile selected. I could easily select the profile for the first session, but when I was starting up the second session, it would just reuse the same profile from the first session.

The solution to this problem is either setting MOZ_NO_REMOTE environment variable to 1, or specifying -no-remote parameter on the command line. The -no-remote parameter on the command line seems to be a recent addition to Firefox, so if it doesn’t work yet for your version of the browser, you’ll need to fall back on to the MOZ_NO_REMOTE environment variable.

So, if you have a recent Firefox version, you need to run (updating your desktop and menu shortcuts seems like a good idea):

[user@host dir]$ MOZ_NO_REMOTE=1 firefox -ProfileManager

If you want to start Firefox with specific profile (e.g.: DesiredProfile), you can do so with

[user@host dir]$ MOZ_NO_REMOTE=1 firefox -P DesiredProfile

Alternatively, you can export the variable globally, by adding the following line to your .bashrc file

export MOZ_NO_REMOTE=1

If you have a recent version of Firefox, then the command changes to:

[user@host dir]$ firefox -no-remote -P DesiredProfile

Other things that you might want to keep in mind are:

Some add-ons will be common between your different profiles. For example, I want to have my delicious bookmarks available to me everywhere. For these cases, you’ll need to install the same Firefox add-on to every profile that you will need it at.
Some bits of configuration (such as custom keyboard shortcuts, for example), will need to be configured in each profile separately.
You might want to have a different Firefox theme for each of your profiles, so that it’s easier to see where you are visually.

Knowing Open Source community pitfalls

I came across this excellent blog post – “Recognizing and Avoiding Common Open Source Community Pitfalls“. It’s very related to the short speech I gave recently over at 3rd Ubuntu / Fedora release party. My angle was on how much good participating in an Open Source project could do to a college student. I was talking more about how much practical stuff one could learn from existing projects – their tools, approaches, etc.

The blog post talks about roughly the same, but from a different perspective. It’s more for those who are starting a new project, rather then joining the existing one. There are plenty of ‘myths’ that go around about how is it is to do Open Source and how everyone can do it, and that all you need to succeed is to start. That’s not so true, of course. There is plenty of stuff to be learned and lots of work to be done. If you are about to start your project or started one recently or just thinking about it, read the article. It’s has roughly a paragraph about each of the following:

Built it and they will come.
Your community will help you build HARD DIFFICULT FEATURE X.
Directional fallacies.
Contributions are free.
Profit models.
Folks can understand your code.
Documentation updates.
Everyone using App X will give back freely and without your asking.
Contributors are like coworkers.
Resources grow on trees.
Cross distribution support is easy.
Users help users and it’s ok to just be a developer.
Cross-project collaboration is easy.

Delete files dialogue in KDE = ugly

As I am getting used to KDE 4 more and more, I am enjoying it more and more. It delivers plenty of visual pleasure while being quite fast and user friendly. However, there this one tiny little thing which annoyed the heck out of me since ancient times. It’s the delete files confirmation dialogue. Every time I select one or more files to delete, here is what I get.

The more files I have to delete and the longer their paths, the uglier it looks. And you know what annoys me the most? It’s that fixing this ugliness is pretty simple. Just collapse and hide the list of files which are about to be deleted, and give a “Details…” button or link to expand the list for those who really care or want to double check. This way, the popup will be much smaller, providing enough of necessary information (“delete” vs. “move to Trash”, and “3 items” vs. “all these items”).

I don’t know how this managed to stay in for so long. Am I the only one who cares about this? Or are there so few KDE developers that nobody has the time to fix this? Do I really need to this myself? I hope not …