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Normally the Linux Magazine has great articles. Impartial, informative and highly technical. Unfortunately, not always. In a recent article, some perfectionist zealot stated that Ubuntu makes Linux looks bad. I couldn’t disagree more.

Ubuntu is a fast-paced, fast-adapted Linux. I was one of the early adopters and I have to say that most of the problems I had with the previous release were fixed. Some bugs went through, of course, but they were reported and quickly fixed. Moreover, Ubuntu has the support from hardware manufacturers, such as Dell, and that makes a big difference.

Linux is everything

Linux is excellent for embedded systems, great for network appliances, wonderful for desktops, irreplaceable as a development platform, marvellous on servers and the only choice for real clusters. It also sucks when you have to find the configuration manually, it’s horrible to newbies, it breaks whenever a new release is out, it takes longer to get new software (such as Firefox) but also helps a lot with package dependencies. Something that neiter Mac nor Windows managed to do properly over the past decades.

Linux is great as any piece of software could be but horrible as every operating system that was release since the beginning of times. Some Linux distributions are stable, others not so. Debian takes 10 years to release and when it does, the software it contains is already 10 years old. Ubuntu tries to be a bit faster but that obviously breaks a few things. If you’re fast enough fixing, the early adopters will be pleased that they helped the community.

“Unfortunately what most often comes is a system full of bugs, pain, anguish, wailing and gnashing of teeth – as many “early” adopters of Karmic Koala have discovered.”

As any piece of software, open or closed, free or paid, free or non-free. It takes time to mature. A real software engineer should know better, that a system is only fully tested when it reaches the community, the user base. Google uses their own users (your granny too!) as beta testers for years and everyone seem to understand it.

Debian zealots hate Red Hat zealots and both hate Ubuntu zealots that probably hate other zealots anywhere else. It’s funny to see how opinions vary greatly from a zealot clan to the other about what Linux really is. All of them have a great knowledge on what Linux is comprised of, but few seems to understand what Linux really is. Linux, or better, GNU/Linux is a big bunch of software tied together with so many different points of view that it’s impossible to state in less than a thousand words what it really is.

“Linux is meant to be stable, secure, reliable.”

NO, IT’S NOT! Linux is meant to be whatever you make of it, that’s the real beauty. If Canonical thought it was ready to launch is because they thought that, whatever bug pased the safety net was safe enough for the users to grab and report, which we did! If you’re not an expert, wait for the system to cool down. A non-expert will not be an “early adopter” anyway, that’s for sure.

Idiosyncrasies

Each Linux has its own idiosyncrasies, that’s what makes it powerful, and painful. The way Ubuntu updates/upgrades itself is particular to Ubuntu. Debian, Red Hat, Suse, all of them do it differently, and that’s life. Get over it.

“As usual, some things which were broken in the previous release are now fixed, but things which were working are now broken.”

One pleonasm after another. There is no new software without new bugs. There is no software without bugs. What was broken was known, what is new is unknown. How can someone fix something they don’t know? When eventually the user tested it, found it broken, reported, they fixed! Isn’t it simple?

“There’s gotta be a better way to do this.”

No, there isn’t. Ubuntu is like any other Linux: Like it? Use it. Don’t like it? Get another one. If you don’t like the way Ubuntu works, get over it, use another Linux and stop ranting.

Red Hat charges money, Debian has ubber-stable-decade-old releases, Gentoo is for those that have a lot of time in their hands, etc. Each has its own particularities, each is good for a different set of people.

Why Ubuntu?

I use Ubuntu because it’s easy to install, use and update. The rate of bugs is lower than on most other distros I’ve used and the rate of updates is much faster and stable than some other distros. It’s a good balance for me. Is it perfect? Of course not! There are lots of things I don’t like about Ubuntu, but that won’t make me use Windows 7, that’s for sure!

I have friends that use Suse, Debian, Fedora, Gentoo and they’re all as happy as I am, not too much, but not too few. Each has problems and solutions, you just have to choose the ones that are best for you.

Gtk, the graphical interface behind Gnome, is very simple to use. It doesn’t have an all-in-one IDE such as KDevelop, which is very powerful and complete, but it features a simple and functional interface designer called Glade. Once you have the widgets and signals done, filling the blanks is easy.

As an example, I wrote a simple dice throwing application, which took me about an hour from install Glade to publish it on the website. Basically, my route was to apt-get install glade, open it and create a few widgets, assign some callbacks (signals) and generate the C source code.

After that, the file src/callbacks.c contain all the signal handlers to which you have to implement. Adding just a bit of code and browsing this tutorial to get the function names was enough to get it running.

Glade generates all autoconf/automake files, so it was extremely easy to compile and run the mock window right at the beginning. The rest of the code I’ve added was even less code than I would add if doing a console based application to do just the same. Also, because of the code generation, I was afraid it’d replace my already changed callbacks.c when I changed the layout. Luckily, I was really pleased to see that Glade was smart enough not to mess up with my changes.

My example is not particularly good looking (I’m terrible with design), but that wasn’t the intention anyway. It’s been 7 years since the last time I’ve built graphical interfaces myself and I’ve never did anything with Gtk before, so it shows how easy it is to use the library.

Just bear in mind a few concepts of GUI design and you’ll have very little problems:

1. Widget arrangement is not normally fixed by default (to allow window resize). So workout how tables, frames, boxes and panes work (which is a pain) or use fixed position and disallow window resize (as I did),
2. Widgets don’t do anything by themselves, you need to assign them callbacks. Most signals have meaningful names (resize, toggle, set focus, etc), so it’s not difficult to find them and create callbacks for them,
3. Side effects (numbers appearing at the press of a button, for instance) are not easily done without global variables, so don’t be picky on that from start. Work your way towards a global context later on when the interface is stable and working (I didn’t even bother)

If you’re looking for a much better dice rolling program for Linux, consider using rolldice, probably available via your package manager.

I’ve been playing with LLVM (Low-Level Virtual Machine) lately and have produced a simple compiler for a simple language.

The LLVM compilation infrastructure (much more than a simple compiler or virtual machine), is a collection of libraries, methods and programs that allows one to create a simple, robust and very powerful compilers, virtual machines and run-time optimizations.

As GCC, it’s roughly separated into three layers: the front-end, which parses the files and produce intermediate representation (IR), the independent optimization layer, which acts on the language-independent IR and the back-end, which turns the IR into something executable.

The main difference is that, unlike GCC, LLVM is extremely generic. While GCC is struggling to fit broader languages inside the strongly C-oriented IR, LLVM was created with a very extensible IR, with a lot of information on how to represent a plethora of languages (procedural, object-oriented, functional etcetera). This IR also carries information about possible optimizations, like GCC’s but to a deeper level.

Another very important difference is that, in the back-end, not only code generators to many platforms are available, but Just-In-Time compilers (somewhat like JavaScript), so you can run, change, re-compile and run again, without even quitting your program.

The middle-layer is where the generic optimizations are done on the IR, so it’s language-independent (as all languages wil convert to IR). But that doesn’t mean that optimizations are done only on that step. All first-class compilers have strong optimizations from the time it opens the file until it finishes writing the binary.

Parser optimizations normally include useless code removal, constant expression folding, among others, while the most important optimizations on the back-end involve instruction replacement, aggressive register allocation and abuse of hardware features (such as special registers and caches).

But the LLVM goes beyond that, it optimizes during run-time, even after the program is installed on the user machine. LLVM holds information (and the IR) together with the binary. When the program is executed, it profiles automatically and, when the computer is idle, it optimizes the code and re-compile it. This optimization is per-user and means that two copies of the same software will be quite different from each other, depending on the user’s use of it. Chris Lattner’s paper about it is very enlightening.

There are quite a few very important people and projects already using LLVM, and although there is still a lot of work to do, the project is mature enough to be used in production environments or even completely replace other solutions.

If you are interested in compilers, I suggest you take a look on their website… It’s, at least, mind opening.

Unix is turning 40 and BBC folks wrote a small article about it. What a joy to remember when I started using Unix (AIX on an IBM machine) around 1994 and was overwhelmed by it.

By that time, the only Unix that ran well on a PC was SCO and that was a fortune, but there were some others, not as mature, that would have the same concepts. FreeBSD and Linux were the two that came into my sight, but I have chosen Linux for it was a bit more popular (therefore could get more help).

The first versions I’ve installed didn’t even had a X server and I have to say that I was happier than using Windows. Partially because of all the open-source-free-software-good-for-mankind thing, but mostly because Unix has a power that is utterly ignored by other operating systems. It’s so, that Microsoft used good bits from FreeBSD (that allows it via their license) and Apple re-wrote its graphical environment to FreeBSD and made the OS X. The GNU folks certainly helped my mood, as I could find all power tools on Linux that I had on AIX, most of the time even more powerful.

The graphical interface was lame, I have to say. But in a way it was good, it reminded me of the same interface I used on the Irix (SGI’s Unix) and that was ok. With time, it got better and better and in 1999 I was working with and using it at home full time.

The funny thing is that now, I can’t use other operating systems for too long, as I start missing some functionalities and will eventually get locked, or at least, extremely limited. The Mac OS is said to be nice and tidy, and with a full FreeBSD inside, but I still lacked agility on it, mainly due to search and installation of packages and configuration of the system.

I suppose each OS is for a different type of person… Unix is for the ones that like to fine-tune their machines or those that need the power of it (servers as well) and Mac OS is for those that need something simple, with the biggest change as the background colour. As for the rest, I fail to see a point, really.

After the buzz on Windows 7 I decided to take a look on a video posted (apparently by Microsoft itself) on youtube.

I was expecting to hear about the new Operating System, only to find out that everything that matters to MS is the Window Manager. No memory or CPU consumption reports, no filesystem or network configuration structure, nothing.

Anyway, I have to talk about the interface then… Now, is it only me or they’re copying what Gnome/Compiz is doing? Because, copying Apple it’s obvious, even Gnome/Compiz is at some extent.

First, window transparency and ALT-TAB with window thumbnails to select with your mouse. Done. Second, dragging icons to the taskbar, what’s new on THAT?!

But now, “something really cool we’re putting in Windows 7 is called ’snap-to’ “?!?!? If I recall right, the graphical interface from the PARC team already had tiled/cascade window arrangement and undoubtedly Microsoft used that on Windows 3, so how is that cool in any way?

Well, they better have a much stabler environment and much lower footprint, otherwise they won’t have nothing really serious to show.

It still hasn’t gone to meet it’s maker, but it was also not as bad as it could’ve been.

After Windows Vista was launched with more PR and DRM than any other, Microsoft hoped to continue its domination of the market. Maybe afraid of the steep Linux increase in desktops (Ubuntu has a great role in that) and other market pressures, they’ve rushed out Vista with so many bugs and security flaws, so slow and with such a big memory and CPU footprint that not many companies really wanted to change their whole infrastructure to see it drawn a little later.

China government ditched it for XP because it was not stable enough to run the Olympics, only to find out that the alternative didn’t help at all.

All that crap helped a lot Linux (especially Ubuntu) jump on the desktop world. Big companies shipping Linux on lots of desktops and laptops, all netbooks with Linux as primary option, lay people now using Linux as they would use any other desktop OS. So, is it just because Vista is so bad? No. Not at all. Linux got really user friendly over the last five to ten years and it’s now as easy as any other.

Vista is so bad that Microsoft had to keep supporting Windows XP, they’re rushing again with Windows 7 and probably (hopefully) they’ll make the same mistakes again. It’s got so bad that the Free Software Foundation’s BadVista campaign is officially is closing down for good. For good as in: Victory!

Yes, victory because in one year they could show the world how bad Vista really is and how good the other opportunities are. Of course, they were talking about Linux and all the free software around, including the new gNewSense platform they’re building, but the victory is greater than that. The biggest message is that Windows is not the only solution to desktops, and most of the time, it’s the worst.

In conjunction with the DefectiveByDesign guys, they also showed how Vista (together with Sony, Apple, Warner et al) can completely destroy your freedom, privacy and entertainment. They were so successful in their quest that they’re closing doors to spend time (and donors’ money) in more important (and pressing) issues.

Now, they’re closing down but that doesn’t mean that the problem is over. The idea is to stabilise the market. Converting all Windows and Mac users to Linux wouldn’t be right, after all, each person is different. But the big challenge is to have users that need (or want) a Mac, to use a Mac. Who needs Windows and can afford to pay all extra software to protect your computer (but not your privacy), can use it. For developers the real environment is Unix, they should be able to get a good desktop and good development tools as well. It’s, at least, fair.

But for the majority of users, what they really want is a computer to browse the web, print some documents, send emails and for that, any of the three is good enough. All three are easy to install (or come pre-installed), all three have all the software you need and most operations and configurations are easy or automatic. It’s becoming more a choice of style and design than anything else.

Now that Apple got rid of all DRM crap, Spore was a fiasco so EA is selling games without DRM, the word is getting out. It’s a matter of time it’ll be a minor problem, too. Would DefectiveByDesign retire too? I truly hope so.

As an exercise to the reader, go to Google home page and search for the terms: “windows vista“. You’ll see the BadVista website in the first page. If you search for “DRM” you’ll also see the DefectiveByDesign web page as well. This is big, it means that lots and lots of websites are pointing to those websites when they’re talking about those subjects!

If you care enough and you have a Google user and is using the personalised Google search, you could search for those terms and press the up arrow symbol on those sites to make them go even higher in the rank. Can we make both be the first? I did my part already.

…and our friend Mauro Persano won in two categories: 2nd on Intel graphics and 5th on best game on the go.

The game, Protozoa, is a retro Petri-dish style frenetic shooting-the-hell-out-of-the bacteria, virii and protozoa stuff that comes in your way. You can play with a PS2 (two-analogue sticks) control, one for the movements and other for the shooting, or just use the keyboard. The traditional timed-power-up and megalomaniac explosions raise even more the sense of nostalgia.

You can download the latest Windows version here but don’t worry, it also runs pretty fine with Wine.

Have fun!

Another fine example about how the open source community can be impressive, even when comparing with the biggest software companies.

Yesterday we had a gig at our annual Music Evening and I needed to edit the videos to upload them on my wife’s website. I go on cinelerra’s website download page and get the Ubuntu 8.04 repository, update the package listing and try to install cinelerra:

sudo apt-get install cinelerra

It should be that easy but unfortunately the repository had an error:

Err http://repository.akirad.net akirad-hardy/main akiradnews 20080417
 500 Internal Server Error
Err http://repository.akirad.net akirad-hardy/main libguicast
1:2.1.0-1svn20080530akirad1
 500 Internal Server Error
Err http://repository.akirad.net akirad-hardy/main libmpeg3hv
1:2.1.0-1svn20080530akirad1
 500 Internal Server Error
Err http://repository.akirad.net akirad-hardy/main libquicktimehv
1:2.1.0-1svn20080530akirad1
 500 Internal Server Error

Well, with nothing else to do about it, I’ve followed the instructions on the website saying to email the guy that put the packages in place, which I did. Seriously, I thought it would take a while (days?) until the guy could have time to go home, do whatever he wanted to do at home, check his emails, talk to the ISP, bla bla bla.

To my surprise, after exactly 1 hour and 20 minutes he replied (in English and Italian) that the packages were reloaded, I should be able to get it, which I did, and indeed, worked absolutely fine. I now have my videos edited.

The “guy” was actually Paolo Rampino, which I thank him very much, but also I’d like to acknowledge once more the power of the open source community. I wonder if I had any much more serious problems (security) with a copy of Windows or Office if Microsoft would take 1:20 hours to not only answer, but to fix it!

Thanks again Paolo, you made another user very happy indeed.

I still code in my spare time and for a while I’ve been gathering some numerical methods I did at university in an easy-to-understand generic C++ package. Despite being easy to understand, I also tried to implement the best method I knew for each problem.

The root finding algorithm is based on Brent’s method which is, in turn, based on the secant method. If everything fails, it throws an exception and you can use the safe bisection method.

The integration is using the Romberg’s method, which is a further extrapolations of Simpson’s method which is already much better than the trapezoid basic method.

For Interpolation I’m using the Natural Cubic Spline but would like to implement other types of splines (like complete, periodical, clamped etc). The interpolation is working, but I couldn’t managed to get the coefficients right yet.

Other codes I have are Monte Carlo, Runge-Kutta and Markov Chain (this one using boost graph library for C++) and will be integrated soon. I’ll let you know when it’s done.

Last week I did two silly but still quite funny projects: word search on protein sequences and chat bot using markov chains.

Word search

Searching for similar sequences among the known proteins to understand evolutionary paths and function similarities is a powerful algorithm called BLAST. Following the same lines I spent a few minutes to develop a similar (but not quite the same) algorithm to search for all dictionary words on all UniProt sequences.

The algorithm will look into a dictionary (say /usr/share/dict/words) and for every sequence it’ll find the words in it, allowing a few (no more than 2) amino-acids to be between the letters. Than it gives a weight to the match based on the size of the word and the “added length” due to additional amino-acids in between. You can also restrict the number of letters on the word list to avoid too short or long words.

The results for 7 to 9 characters words in English searched only on Swiss-Prot entries are:

STRANGE  1.4
CHARADE  1.75
SLEDGED  1.75
MEALIER  1.75
DEMEANS  2.33333
DETAINS  2.33333

Markov bot

I knew a markov chain could have true wisdom but I never tried to make it actually talk to anyone until a friend told me about MegaHAL (much better than my markov model, of course). I decided to give it a try and got the XMPP bot from the Python examples and plugged in my markov program on all phrases spoken to it.

In the beginning it was awful, of course, it knew nothing. But with time (and hard work from some friends to actually teach him about leisure, programming, physics etc) it could babble a few coherent words once in a while.

The results are complete rubbish, below is a sample of the complete non-sense conversation I had with it now:

rengolin: how are you doing? have you managed to find the answer to Life, The Universe and Everything?
oraculoids: with an amazing company makes the basic points of some operator
rengolin: operator or not, you must come to reality and sense the danger there is in talking like that after such a complex and meaningful question
oraculoids: dead as an interface to follow an animal
rengolin: whatever animal you prefer, I would say but it seems that you are now driving the conversation
oraculoids:
rengolin: aha! I know you didn’t have answers to everything!
oraculoids: how is in between and pray
rengolin: I don’t pray too much, really, I’m not that kind of a person anyway…
oraculoids: but at the conversation it’t fall into them!
rengolin: I would never say that, especially not with you my friend
oraculoids: A design pattern is a practical laywer
rengolin: lawyers have no purpose other than screwing up the poor
oraculoids: hi bot
rengolin: I am not a bot
oraculoids: field of some of life, love them!

Quite stupid, I might say, but still I had a lot of fun doing it and that’s what matters… In spite of that, though, megaHAL is quite an impressive program and BLAST is a very powerful search mechanism.

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