Stories tagged Linux:RSS Feed

Versteckte Dateien; tags=Linux, Kurios

Möchte ich eine Datei unter unix/Linux verstecken, so verwende ich den Punkt '.' als Prefix. Gewohnheit für den Anwender, einfach zu merken. Das geht mittlerweile ganz automatisch.

Aber irgendwann stellt man sich die Frage «Warum?». Jedenfalls habe ich mir diese Frage gestellt. Der Dateityp wird aus dem Inhalt ermittelt (jedenfalls meistens). Zugriffsrechte funktionieren über Filesystem Flags. Der Dateiname scheint ein frei zu vergebender Name zu sein. Bis es eben zum Verstecken geht.

Logisch? Intuitiv? Nicht wirklich. Eigentlich erweckt es eher den Eindruck eines Hacks. Irgendwann hinzugefügt, als das Filesystem bereits fertig und nicht mehr zu ändern war.


-- Christoph Egger <christoph@coders-nemesis.eu> Mon, 19 Jan 2009 17:33:27 +0100

Unknown Horizons 2009.0; tags=Programmieren, Unknown-Horizons, Linux, FOSS

Unknown Horizons Logo

Unbestätigten Insiderinformationen (/me ist Teil des Teams) zufolge steht die Veröffentlichung von Unknown Horizons 2009.0 in wenigen Minuten an.

Nach über 5 Monaten Entwicklung hat das Unknown Horizons Projekt jetzt ein neues Snapshot Release in der Version 2009.0 herausgebracht. Nachdem wir heute Nachmittag Pakete gebaut und den letzten Feinschliff vollendet haben, durfte ich das neue Release im SVN tree des Projekts taggen.

Neben der Namensänderung sind jetzt auch erstmals Graphiken in einer ordentlichen Auflösung dabei, sowie eine deutlich ansprechendere Spielwelt -- keine quadratischen Inseln mehr! -- so dass die Hoffnung bleibt, dass möglichst viele Nutzer Gefallen an dem Spiel finden werden.

Eine weitere, wichtige Neuerung ist der Free Trader. Somit ist es jetzt möglich im Singleplayer Modus (Multiplayer müsste irgendwann implementiert werden) Waren zu kaufen/verkaufen.

Was hat es dann nicht in die neue Version geschafft? Leider eine ganze Menge -- das Release ist nunmal nicht zu Unrecht als Alpha gekennzeichnet. Meine Ziele für die nächste Zeit sind allerdings dann i18n/l10n, was leider von PyChans Fähigkeit abhängt Unicode Zeichen darzustellen, und saubere Installierbarkeit, sodass ich offizielle Debian Pakete bauen kann.

Wer sich für Details interessiert, der sei auf das Changelog verwiesen.


-- Christoph Egger <christoph@coders-nemesis.eu> Sun, 08 Mar 2009 20:28:30 +0100

[Review] AI Touchbook; tags=Debian, Linux, FOSS, Uni

Having my primary working Computer, a Lenovo Thinkpad, going into repair at the end of December I finally got up to ordering on of those TouchBook ARM based netbooks I was looking at for some time. After some processing time it finally got shipped in April and arrived here last Monday, time to write up my first impressions.

Some words about the Hardware. The TouchBook ships with a so called "Beagle Board" featuring a OMAP3 Processor, ARM Cortex A8 running at 600MHz, 512MiB of RAM and a 8GiB SD Card for storage. It has a 8.9" touch screen and comes with USB and Bluetooth Sticks for wireless connectivity. The Display part contains all the needed Hardware and is detachable from the bottom that is just a keyboard sitting on the secondary Battery. You can open the Top to get at 4 intern USBs (3 USB-A and one Mini-USB) where 2 of these spots are occupied already for wireless networking and Bluetooth.

First experience

The TouchBook comes with an US Power Adaptor only so when I got the device I was running for some tiny Adaptor to get the plug into a normal EU Power Outlet (it's incredibly hard to get one for this Direction while it's easy to get some travelling stuff to plug EU Hardware into various different Outlets!).

When I finally booted it the first thing you'll notice is the touch interface for the bootloader. That's quite a difference to all-text-based old grub! The shipped SD Card offers 3 Operating Systems, one custom Linux that might well be interesting to the average User, a Ubuntu Karmic that really OK for a Debianoid Hacker- both running a XFCE Desktop - and a Android that is really slow and doesn't seem to be good at anything. Needless to say I sticked with the Ubuntu for now.

What to not expect

Well this is a 600MHz CPU with half a Gig of RAM running of a SD Card. So don't expect it to be good at anything that can profit from today's High-End Hardware.

The good Points

First of all, I have to admit that the touch screen is a neat interface, way superior to the Touchpad Area you'll normally find on a Notebook - at least if you use the stylus. It's quite different from the inside-the-keyboard trackball the thinkpads have of course.

The Website claims 10h of Battery life and while I've emptied the battery much faster under certain workloads (e.g. Playing cards) it does hold that promise with emacs fired up in org-mode, IRCing on a server over SSH and the mandatory wireless working. Same for a always-on on campus day which just works.

Again putting the screen on the keyboard the wrong way 'round will give you a touchscreen tablet with the keyboard out of your way, an ideal configuration for playing. And I have to admit playing games like gtkballs or aisle riot real fun. So much fun actually I'm currently thinking on whether it would be feasible to get openpandora working on it.

What I'm really missing

There are two Properties that are really lacking from the device which would make it (in my personal opinion at least) a whole lot better: A simple Ethernet controller I could use to go online when sitting in the server room doing some maintenance without taking my WRT with me and some slot to store the stylus when not using it where it's easy to get out (currently I'm having it in my wallet).

Then there's something (maybe a Kernel Bug): The Wireless is unable to find any new Access Point after disconnecting from some and walking out of reach from that. Force-unloading the kernel module and waiting 30 minutes worked for me multiple times but that's purely inacceptable.

Finally there are some minor glitches. The shiny red cover just gets dirty every time you touch the thing and the Keyboard is really small (what a surprise on a 9" device) and has some of the special Keys (like the Home key) located at unusual spots (Page-Up/Down only available through the FN modifier). Shift and End at the right side are also labeled opposite from their actual function (at least on Ubuntu).

The last ugliness is the top part battery only charging when the device is running, which means you"ll have the TouchBook running all night to get the battery charged and the Battery Monitor not working at all (at least in the current version of the operating systems).

Where to go now

I've not yet come around to really play with the operating system (apart from installing wicd, urxvt-unicode and awesome getting the most needed of my working environment). As I'm a Debian Developer I'll definitely need a Debian running on it (although I was told it'll be slow with software compiled for armv4te) and, as it needs to be running all night anyway, I'll try out gentoo pending another SD Card for experiments.

Secondly there's currently no useable conforming Common Lisp Implementation in Debian for armel as far as I can tell. As arm was already working it shouldn't be that hard, let's see if I can change that but feel free to join me!

Final Notes

I was thinking of some mobile-ish note-taking device and remote ssh terminal for University which the device clearly can do even for 10h away from any power plug while being some non-standard non-x86 device to toy on (It's actually my second armel next to the sheeva plug mounted on my window board.

As a final Remark: This blogpost was written on the TouchBook hacking some markdown into emacs while traveling by train to Erlangen where I study on Sunday Night after having read some chapters of Cory Doctorow's Little Brother on my E-Slick E-Book reader and finished later in my Room.

Maybe I'll find some time to write a review for this device as well one day!


-- Christoph Egger <christoph@coders-nemesis.eu> Mon, 26 Apr 2010 10:32:35 +0200

[FAIL] Security; tags=Programmieren, Linux, FOSS, Rant, Fail

I'm all for security and really like encryption (my Notebook's harddrive is encrypted, I've recently got a GPG Smartcard, ...) but sometimes you see big failes where security is atemted but doesn't actually secure anything but only hinders the legitimate user.

Today one of these candidates ate way to much of my time again. I'm currently getting more and more used to GNU Emacs and currently experimenting with emacs-jabber. Therefore copying my jabber accounts over from psi. As with these passwords you never type in I couldn't remember some of my jabber passwords -- no problem psi has to store them so it should be easy to get them, right?

Well actually not. The configuration file (XML) had a password entry but all that was in it was just obviously hex-encoded numbers. These numbers turned out to be be 16bit packages of characters that are XOR-ed against the JID So now you have to read them in in junks of 16bit, XOR them against the JID and get the password.

Time to recapitulate what this security helped. I've written a hacky 10 lines C Program that can reliably retrieve passwords from any config file I might come across. Seems you can do the same in 2 lines of perl. Ergo no security at all was added.

Next question: What did it cost? Needed an hour or so of researching the encryption and trial&error out the right program fragment. For nothing gained at all. Fail.


-- Christoph Egger <christoph@coders-nemesis.eu> Wed, 02 Jun 2010 20:23:08 +0200


valid XHTML, CSS -- Django based -- ©2008 Christoph Egger