Posts filed under 'IT'

Emacs 23.1, bitches!

The first official 23.* version of the popular text editor Emacs has been released. Well, “text editor” is almost a reduction of functionality, as Emacs has thousands of commands to accomplish the most unthinkable tasks.

Emacs 23.1

From the official announcement:

Here are some new features of Emacs 23.

– Improved Unicode support (the internal character representation is now based on UTF-8).

– Font rendering with Fontconfig and Xft.

– Support for using X displays and text terminals in one session, and for running as a daemon.

– Shift-selection.

– Smarter minibuffer completion.

– Per-buffer text scaling.

– Directory-local variables.

– New packages for:
* viewing PDF and postscript files (Doc view mode)
* connecting to processes via D-Bus (dbus)
* using the GNU Privacy Guard (EasyPG)
* displaying line numbers in the fringe (Linum mode)
* editing XML documents with on-the-fly validation (nXML mode)
* editing Ruby programs (Ruby mode)
* display-based word wrapping (Visual Line mode)

3 comments July 31st, 2009

Why free software shouldn’t depend on Mono or C#

Some days ago, the Free Software Foundation published a short, very interesting article by Richard Stallman that claims, as summarized in the title, that the FOSS community should not pursue the patent-encumbered way of the compatibility with closed minds.

This is not to say that implementing C# is a bad thing. Free C# implementations permit users to run their C# programs on free platforms, which is good. […] The problem is not in the C# implementations, but rather in Tomboy and other applications written in C#. If we lose the use of C#, we will lose them too. That doesn’t make them unethical, but it means that writing them and using them is taking a gratuitous risk.

Full article here:

2 comments June 29th, 2009

Personal Gentoo overlay on

It’s a few weeks now that I’m keeping my personal Gentoo overlay on github. I’m uploading there some ebuilds that I need, usually to fix bugs corrected only on Bugzilla, to bump recent packages or anything that is not yet in the official Portage tree or in any of the popular overlays that I use.

If you wish to use it, just clone it somewhere in your disk with
git clone git://
and add the fetched folder to your PORTDIR_OVERLAY.
If you have any comments, please let me know 😉

Add comment June 20th, 2009

WoW, this is just… wow!

Dopo l’atterraggio in collegio delle prime sottoscrizioni a pagamento (del piano) per i server ufficiali di World Of Warcraft e mio seguente, ovvio, stretto interessamento (limitato alle sole osservazione e partecipazione morale, per vari motivi), non potevo non dedicare un breve post al GDR online più accattivante di tutti i tempi (nonostante io lo usi come metro, negativo, di comparazione della versione 4 di Dungeons & Dragons, tutta abilità e tempi di cooldown), che non sembra soffrire problemi di età o sovrappopolazione. Anzi, scherzando (ma non troppo), immaginavo con i miei colleghi di collegio gli esperimenti sociologici che si potrebbero fare su una tanto vasta quantità di personaggi e giocatori. Alcuni test, molto semplici, sono già stati condotti nell’Auction House. 😉
I video introduttivi del gioco originale e delle due espansioni (The Burning Crusade e Wrath of the Lich King) dopo il readmore.

Four years have passed since the mortal races banded together and stood united against the might of the Burning Legion. Though Azeroth was saved, the tenuous pact between the Horde and the Alliance has all but evaporated. The drums of war thunder, once again.

Illidan Stormrage racconta la sua vicenda:

Imprisoned for ten thousand years, banished from my own homeland… and now you dare enter my realm? You are not prepared… YOU ARE NOT PREPARED!

Terenas Menethil parla a suo figlio Arthas (protagonista del video):

My son, the day you were born the very forest of Lordaeron whispered the name… Arthas. My child, I watched with pride as you grew into a weapon of righteousness. Remember, our line has always ruled with wisdom and strength and I know you will show restraint when exercising your great power. But the truest victory, my son, is stirring the hearts of your people. I tell you this: for when my days have come to an end, you shall be… king!

3 comments May 8th, 2009

Avoid Skype crash with video conversation on Linux

There is a recurring problem that (used to) annoy me when I tried to use my webcam with Skype on Linux. Being a proud owner of a

00:02.1 Display controller: Intel Corporation 82852/855GM Integrated Graphics Device (rev 02)

the number of Xv ports that the display driver (xf86-video-intel) exports to the applications is quite limited:
$ xvinfo | grep ports
number of ports: 1

Yep, only one, not enough to show both the incoming and the outgoing video stream. Skype underlines the problem by printing
Xv ports available: 1
on the console and, most importantly, by crashing whenever I try a full-duplex video conversation.

The workaround I found this evening is quite simple and I wonder why my previous attempts were unable to hit the target:

  1. Establish the audio conversation with the counterpart.
  2. Enable my own video stream: I see the video thumbnail and the peer starts receiving my image.
  3. Disable the local visualization of my video stream: I no longer see the preview, but the counterpart still receives my video. More importantly, the video resource (the Xv port) is still held by the application, so the attempt to show a new video window, in this moment, would crash Skype.
  4. Stop streaming my own video: the peer no longer sees my image. Probably Skype releases the Xv port in this moment.
  5. Ask the peer to start streaming his/her image: Skype allocates the (now free) Xv port to the incoming video, thus showing the counterpart data.
  6. Restart my video stream: Skype remembers that I desired not to see my preview in the current session, so no allocation attempt takes place, thus no crash.

Maybe there are some variations of the algorithm that work as well, but that’s enough for me 🙂 (and this method is almost transparent to the counterpart).

3 comments April 17th, 2009

Why undecidable problems must exist

[..] it is quite easy to see why almost all problems must be undecidable by any system that involves programming. Recall that a “problem” is really membership of a string in a language. The number of different languages over any alphabet of more than one symbol is not countable. That is, there is no way to assign integers to the languages such that every language has an integer, and every integer is assigned to one language.
On the other hand programs, being finite strings over a finite alphabet (typically a subset of the ASCII alphabet), are countable. That is, we can order them by length, and for programs of the same length, order them lexicographically. Thus, we can speak of the first program, the second program, and in general, the ith program for any integer i.
As a result, we know there are infinitely few programs than there are problems. If we picked a language at random, almost certainly it would be an undecidable problem. The only reason that most problems appear to be decidable is that we rarely are interested in random problems. Rather, we tend to look at fairly simple, well-structured problems, and indeed these are often decidable. However, even among the problems we are interested in and can state clearly and succinctly, we find many that are undecidable […]

from Introduction to Automata Theory, Languages, and Computation, by J. E. Hopcroft, R. Motwani, J. D. Ullman

Add comment March 8th, 2009

Bash 4.0 released

The fourth major version of the popular Unix shell, bash, has been released.

This release fixes all the outstanding bugs and introduces some new functionalities: associative arrays, improvements to the programmable completion functionality, case-modifying word expansions, co-processes, support for the ‘**’ special glob pattern (that matches all directories and files within them, when appropriate, recursively) and additions to the shell syntax and redirections (like ‘|&’ as a synonym for ‘2>&1 |’, that I use frequently).
You can read the official announcement here.


1 comment February 24th, 2009

UNIX time about to reach 1234567890

In a few days, the UNIX time will reach quota 1234567890.
You can try and see the exact second in which this event will happen on your machine by running in a shell:
perl -e 'print scalar localtime(1234567890),"\n";'
For all of those (like me) who live in GMT+1 (CET) the output should be:

$ perl -e ‘print scalar localtime(1234567890),”\n”;’
Sat Feb 14 00:31:30 2009

I assure you that I will be eagerly waiting for that moment.
(whatever the reason)

Thanks Slashdot for reminding me.

Add comment February 9th, 2009

Sandboxing FAIL @ Polito

Gli studenti del Politecnico di Torino già conoscono le mitiche macchinette blu (i “totem”) che permettono di stampare statini, certificati ed eseguire semplici operazioni di segreteria. I medesimi studenti sanno anche che detti computer sono sandboxed, cioè le azioni che l’utente può compiere sono limitate a quelle che i sistemisti considerano accettabili: browser personalizzato con accesso alla sola rete interna, applet Java dedicati per l’uso dei servizi di segreteria, eccetera…
Uhm… ne siete davvero sicuri? 🙂



Mentre ero lì che stampavo statini per gli esami di questo periodo è comparso un piccolo pop-up che mi chiedeva s’io volessi aggiornare Adobe Acrobat Reader all’ultima versione disponibile. Avrei potuto lasciarmi scappare un’occasione del genere? Ancora una volta, no 🙂 Sono andato avanti nell’esplorazione, assieme agli amici della compagnia della nerdizia (di Strategia ed Innovazione).
Rispondendo affermativamente alla richiesta si è aperta una pagina del sito della Adobe. Innanzitutto abbiamo scaricato l’aggiornamento suggerito, che ci ha dato accesso alla finestra dei downloads di Firefox (ancora sandoboxato). La finestrella riporta un collegamento al Desktop; cliccandoci abbiamo fatto comparire la barra delle applicazioni di Windows, che però non rispondeva ai comandi.
Finestra downloads di Firefox

Non ci siamo arresi.
La ricerca nel sito della Adobe era gestita da Google, quindi in basso alla pagina c’era un altro link al sito del motore di ricerca; il target del link era molto probabilmente _blank, quindi si è aperta una nuova finestra di Firefox, con tutti i menu e le barre al loro posto.
Google sulle macchinette

Una volta avuto accesso a quello è stato facile. Innanzitutto abbiamo provato siti di vario genere, come Youtube (segue foto con in bella vista un video sui LOLCATS).
Lolcats su Youtube

Seguendo i suggerimenti di mamma Google, abbiamo scaricato ed installato con successo Google Chrome (vedere sotto per un’immagine), dimostrando che l’utente costantemente loggato gira con i privilegi di amministratore. Ed a quel punto la barra delle applicazioni ha iniziato a rispondere ai click. Abbiamo aperto il menu Start ed un prompt dei comandi (per gradire), come dimostrato nella prima foto del repertorio.

Lezione del giorno: un altro punto a sfavore del sistema informatico del Poli (questa volta la parte hardware, ma si somma alla precedente figuraccia); un punto, invece, guadagnato dagli infaticabili smanettoni di Ingegneria Informatica 😛

AGGIORNAMENTO: all’uscita dal laboratorio, alla fine dello studio, siamo ripassati davanti al totem. La pagina web non era quella che avevamo lasciato, ma il sistema era ancora in uno stato di palese vulnerabilità. Amanti come siamo della ricorsione, abbiamo scattato un’ulteriore foto, questa volta in Chrome, visitando un sito… molto particolare 🙂

Blog in Chrome

8 comments January 27th, 2009

udp2tcp-0.0.2 released

A new version of udp2tcp has been released today. Changes include:

  • Usage of GCC function attributes
  • Refactoring of the folders scheme to a better one
  • Refactoring of the filters code and migration to a different scheme
  • Addition and improvement of the command-line parsing function
  • Makefile enables debug info in the object files

Link to the project:
Download here:

Add comment June 15th, 2008

Next Posts Previous Posts



September 2019
« Feb    


Posts by Month

Posts by Category

What's played in the cave