Steffen's Tech Blog

Two weeks ago I upgraded to Ubuntu 8.10 (Intrepid Ibex). The upgrade went nice and smoothly and I really like the new version (especially the improvments made in KDE). The only problem I realized afterwards was that the Skype audio settings wasn't working correctly by default. Some manual adjustments were necessary. After I have done these adjustments already several times (two PC's, GNOME and KDE), I thought it might make sense to write them down. Maybe these settings that worked for my PC's will be helpful somebody else. adjust the skype sound device options as shown in the following screenshot: adjust the Ubuntu audio settings (Volume control) according to the next 4 screenshots:

The newest version of my favorite Linux distribution ...

Following the instructions on KDE 4.1.1 Release News I updated to KDE 4.1.1 on my Kubuntu 8.04 Hardy Heron PC. Some of the instructions were a little confusing: enable "Recommended Updates (backports)" in "Software Sources" --> as "backports" are also used to describe "Unsupported updates" (--> which is not recommended for a productive system), it must be a mistake There is no authentication key for the repository containing the updated packages deb http://ppa.launchpad.net/kubuntu-members-kde4/ubuntu hardy main . This results in warnings when updating packages from this repository which leave some kind of uneasiness as using authentication keys seem an useful security measure. Besides this, the update worked well and I found now KDE 4.1.1 much more stable than KDE 4.0. In addition, most of the functionality that I used in the GNOME desktop is available. Furthermore  I like the new KDE look as well as some of its new applications (as alrea...

Two weeks ago my MacBook wouldn't start because of a hard disk defect. As the Macbook still was within the warranty period, I took it to the nearest Apple authorized service provider A.S.T.I. GMBH AGENTUR FÜR SYSTEME (that I have found via http://www.apple.com/de/buy/locator/index.html ), where they replaced the HD. At home, I restored my Macbook HD content (that furtunately had been regularly backed up via Time Capsule) with the following steps (based on http://support.apple.com/kb/HT1177 ): Install the system from the Mac OS X 10.5 Leopard DVD Restart the Mac Connect Time Capsule via an Ethernet cable with the Macbook Click "From a Time Machine backup or other disk." when asked if you want to transfer information from another Mac or volume (in the Do You Already Own a Mac?" window). Click Continue Select Time Capsule when it appears as a Backup Volume and click Continue The Macbook starts to check the Time Machine backup and the "Transfer Your Information...

Recently I needed a tool to modify PDF files and afterwards merge these files into one file. I ended up using the following tools: Inkscape Inkscape is a free and open source vector graphics editor that can be used - among lots of other functions - to modify a single PDF page (e.g. add text). AccessPDF - Pdftk the PDF Toolkit. Pdftk is a free and open source easy to use command line tool for: * Merge PDF Documents * Split PDF Pages into a New Document * Decrypt Input as Necessary (Password Required) * Encrypt Output as Desired * Fill PDF Forms with FDF Data and/or Flatten Forms * Apply a Background Watermark * Report on PDF Metrics such as Metadata, Bookmarks, and Page Labels * Update PDF Metadata * Attach Files to PDF Pages or the PDF Document * Unpack PDF Attachments * Burst a PDF Document into Single Pages * Uncompress and Re-Compress Page Streams * Repair Corrupted PDF (Where Possible) e.g. the following example Merges Three PDFs...

What is BlogThis! ? : "BlogThis! is another easy way to make a blog post at your Blogger blog. Just add the BlogThis! link to your browser's toolbar. Clicking this opens a mini-interface to Blogger prepopulated with a link to the web page you are visiting, as well as any text you have highlighted on that page. Add additional text if you wish and then publish or post."

Recently, I spent some time to search for free, open-source alternatives for commercial mathematics programs such as Matlab and Mathcad. By far the most promising software I have found was Sage. Sage combines the power of many (currently 71) existing open-source packages into a common Python-based interface. It can be used to explore mathematical constructions in algebra, geometry, number theory, calculus, numerical computation, etc. The combination of proven open-source packages (including excellent Python packages such as Numpy, Matlibplot, Scipy and Sympy) and an excellent web browser based entry of formulas and plots in worksheets called notebooks. The usage of Python as the glue that holds all packages together provides several advantages. First you have the full power of python available in Sage. Second, you don't need to learn another specialized script language that you would otherwise not need. Excellent screencasts together with good tutorials and documentation pages p...

After reading the following article about the status of the GNOME project http://wingolog.org/archives/2008/06/07/gnome-in-the-age-of-decadence I decided to check out the KDE 4 desktop by installing the "kubuntu-kde4-desktop" package (via Adept or apt-get) and I have to admit: I really like the new KDE 4 desktop. A lot of improvements have been made compared with its predecessor. I especially like the new version of the image viewer Gwenview and Okular, KDE4's document viewer. Check out http://www.kde.org/announcements/4.0/applications.php for more details. Unfortunately, the KDE 4 desktop seem not to be stable enough for production use. At least I experienced some crashes that required reboot via " R aising E lephants I s S o U tterly B oring" . In addition, I missed some functionality. Therefore I can't recommend switching to KDE4 right now. But I decided to give it another try as soon as KDE4.1 is available from the Ubuntu repositories in the hope that ...

Today I decided to switch to the newest version of the ATI driver flgrx (version 8.6) instead of the restricted driver that comes with the ubuntu 8.04 distribution. I followed the excellent description on http://wiki.cchtml.com/index.php/Ubuntu_Hardy_Installation_Guide . Everything worked fine. I could enable "Extra Visual Effects" without having problems with the video drivers e.g. in Miro (after I changed from xine to gstreamer).

Finally, I decided to buy the newest version of Mac OS X. The main reason was that I liked to have a professional backup solution for my macbook especially after the trouble I had before on my Windows desktop (see my previous post from April 2008 ) and Time Machine together with Time Capsule seem to be exactly what I was looking for. The installation of Mac OS X was smoothly. Everything worked as expected. Even my synchronization via the python rsync script worked. Time Machine setup together with Time Capsule are really amazing simple and effective. There are many more nice little features in Mac OS X Leopard. Check out http://www.apple.com/mac/ for more. In my point of view, it is definitely the best operating system I know. Once more, Apple products fulfilled my expectations and are worth their price.

Application: Firefox 3.0 (2008060309) Operating System: Linux (x86-gcc3) Adblock Plus 0.7.5.4 Ads were yesterday! Adblock Plus: Element Hiding Helper 1.0.5 Helps you create element hiding rules for Adblock Plus to fight the text ads. Answers 2.2.48 Alt+Click on any word or term for quick info (definitions, up-to-the-minute reference, and more). No selection is necessary! Deutsches Wörterbuch 1.0.1 DOM Inspector 2.0.0 Inspects the structure and properties of a window and its contents. Extension List Dumper 1.14.1 Dumps a list of the installed extensions. Finjan Secure Browsing 1.314 Secure Browsing by Finjan Firebug 1.2.0a21X Web Development Evolved. FireGestures 1.1.2 Executes various commands with mouse gestures. Flagfox 3.2.6 Displays a flag depicting the location of the current server Forecastfox 0.9.7.6 Get international weather forecasts and display it in any toolbar or statusbar with this highly customizable extension. FoxyTunes 3.0.1.1 Control any media player from Firefox and m...

See also my post on [ubuntu] Celtx on Hardy - Ubuntu Forums Celtx is a nice media pre-production software with features you need to take your story from concept to production. Install Celtx as root in order to let all users on your Ubuntu machine have access to it (see also http://wiki.celtx.com/index.php?title=Installation ). After this you should be able to start Celtx with: sudo /usr/local/celtx/celtx In order to be able to start celtx without sudo, remove the subfolders .greyfirst and .celtx as described in the celtx wiki. These hidden folders are in your home directory (~) and - as you have installed Celtx as root - you can only remove them as root. One way to do this is to start Nautilus as root with: sudo nautilus Select your home folder, choose "show hidden files" (CTRL + H) and remove both folders. Afterwards, any user should be able to run celtx using: /usr/local/celt/celtx In order to launch Celtx from an icon, add a custom application launcher. BTW - After http://...

Yesterday, I needed my scanner the first time after installing Ubuntu 8.04. In Ubuntu 7.10 I could use the scanner as normal user with xsane. Now running xsane let to the following error message: Segmentation fault whereas running xsane as root with sudo xsane works. The following shows the current status of my investigation. sane-find-scanner let to the following output: # sane-find-scanner will now attempt to detect your scanner. If the # result is different from what you expected, first make sure your # scanner is powered up and properly connected to your computer. # No SCSI scanners found. If you expected something different, make sure that # you have loaded a kernel SCSI driver for your SCSI adapter. found USB scanner (vendor=0x04a9 [Canon], product=0x221c [CanoScan], chip=GL842) at libusb:006:008 # Your USB scanner was (probably) detected. It may or may not be supported by # SANE. Try scanimage -L and read the backend's manpage. # Not checking for parallel port scanners. # ...

Ubuntu 8.04 automatically detects connected hard drives (such as a second drive with an NTFS partition). NTFS hard drives are not mounted automatically by default in Ubuntu 8.04. Instead they need to be mounted manually e.g. via clicking onto them in Nautilus. Sometimes it is desirable that such a NTFS drive will be automatically mounted at login (e.g. when you want to run a script that uses these drives at startup). This can be done via: 1) Make a mounting point for that drive sudo mkdir /media/Backup_HD Note: Replace "Backup_HD" with whatever name you like. 2) Edit /etc/fstab: sudo gedit /etc/fstab 3) Add the following text in fstab: /dev/sdb1 /media/Backup_HD ntfs defaults,locale=en_US.UTF-8 0 1 Note: Replace "/media/Backup_HD" with the name you choose in the 1st step. Furthermore, replace "/dev/sdb1" with the actual value for the hard disk you want to mount automatically. Note: If you don't know what value you should use instead of "/dev/sdb1...

If you like KDE besides Gnome on your Ubuntu installation just follow the tutorial How to install KDE on Ubuntu and type sudo aptitude update && sudo aptitude install kubuntu-desktop in the terminal to install Kubuntu.

Recently I bought an Desktop PC Inspiron 530 from Dell with Ubuntu 7.10 pre-installed to replace the very old Window PC that my parents used. I immediately upgraded the system to Ubuntu 8.04 and installed a subset of the additional software mentioned in my last post. In addition to this, I wanted to use a wireless network connection to avoid cables from the router to the PC (both are in different rooms). Therefore I bought a Belkin Wireless G USB Network Adapter F5D7050 v4002 uk (USB ID 050d:705c) together with the Dell PC. It was disappointing that the included documentation only explained how to install and use the Network Adapter in a Mircrosoft environment, so that I had to search the Web about how to install wireless network adapters in Ubuntu. I found links such as https://help.ubuntu.com/community/WifiDocs/WiFiHowTo , http://linuxwiki.de/LinuxWireless or http://wiki.ubuntuusers.de/WLAN . According to these pages, wireless still isn't always trivial using Linux and theref...

After installing Ubuntu 8.04 LTE (for the reasons mentioned in my previous post ), I started customizing this machine so that all my periphery devices are supported again and all additional software will be added and configured to my needs. Printer setup First, my printer should work again on my Ubuntu machine. I have bought my SAMSUNG CLP-300 Colour Laser Printer because of its good price/performance ratio and its platform independence (Windows, Mac OS X and Linux support was advertised). I used the closed-source driver from Samsung (current version is CLP-300 Unified Linux Driver ver.2.00.97 ) before. Now, I followed the recommendation on OpenPrinting database of Linux Foundation to give the open source printer driver foo2qpdl a try (following the short installation instruction on that site). Printing a test page and printing from Firefox worked immediately. Strangely, printing from OpenOffice needs some additional work as it didn't work. It is described in the section "S...

11 days ago my boot hard disk crashed during some Norton Antivirus scanning in Windows XP. My desktop PC is a Fujitsu-Siemens Computer Scaleo T A64 XP 50 AM2 0 2,0GB bougth in 2006. I had Windows XP installed on the original Sigate 320GByte disk that contained also all my data (as I wanted to use the same files from both Windows and Ubuntu and Windows can't write on the Ubuntu file system but Ubuntu can write on the Windows NFTS format). In addition I had installed a 400 GByte harddisk with a backup partition and my Ubuntu installation. The bios couldn't find the Sigate disk any longer and as this disk contained the boot loader - neither the Windows XP nor my Ubuntu 7.10 did start. An clicking noice confirmed that there was a serios problem with the Sigate disk. What to do? As I have a three-year service contract from Fujitsu-Siemens I first contacted the Fujitsu-Siemens service via the service phone I found under http://www.fujitsu-siemens.com . They aggreed to send somebody...

XULRunner is an interesting runtime environment developed by the Mozilla Foundation for providing a common back-end for XUL applications as rich as Mozilla Firefox or Songbird . There is a nice getting started tutorial available. It starts with explaining how to download and install XULRunner. If you are using Ubuntu open the Synaptic Package Manager (Top panel: System --> Administration --> Synaptic Package Manager) and search for xulrunner and install the most current version. If you can't find the xulrunner package, make sure that you have checked "Community-maintained Open Source software (universe)" from Ubuntu "Software Sources". Follow step 3 to 8. You should now see a window that looks something like this screenshot taken from Ubuntu Gutsy 7.10.

Ever considered to make your Ubuntu installation even more secure? There is an excellent chapter available in the official Ubuntu documentation called "Keeping Your Computer Safe" that is worth to read. I used its sub chapter "Set up a firewall" to install the firestarter package - an Open Source visual firewall program that combines ease of use with powerful firewall features. To understand its basic features and how to use them you can read the quick tutorial from the Firestarter Online Manual . After completing the start wizard, some services that you might have on your machine such as a web server or a SSH server will not be reachable any longer from the outside because the default configuration set up provides strong protection against incoming intrusions. E.g. the connection from my Macbook via SSH to my Ubuntu machine wasn't possible any longer and therefore my rsync script described in my previous post " Synchronize files between a Macbook and an...

If you are using the Mozilla Firefox Web browser, you can also use ScribeFire to post your blog easily from within the browser. It allows you to drag and drop formatted text from pages you are browsing, take notes, and post to your blog. You can even add easily labels to your post. Everything works very fast. As Firefox is a cross-pattform browser, you can use it on Linux/Mac/Windows. You can read more about ScribeFire on http://www.scribefire.com/ where you can also find the link to install it from the Mozilla Add-ons site. Somehow the length of the posts seem to be limited as I have noticed that longer posts (such as my post from March 4, 2008) will be not loaded completely in the ScribFire Editor, but I haven't found any information about the maximum allowed length of a post.

Another easy way to post a message to Blogger is using Google's Dashboard Widget for Mac. Its very basic text formating ( bold and italic ) should be sufficient if you want just post some short lines to your blog without advanced formating, links, images, media files, spelling check. In that case it is much faster than having to start first a browser or a full-blown desktop application. What I am missing is the feature to add labels for the post, so if you want to add labels you need to do this later directly in Blogger. Blogger Dashboard Widget for Mac is available from http://www.google.com/macwidgets/index.html .

As I did use different computers at home (mainly Ubuntu and Mac OS) to write the post, I did appreciate that the document was always online although I had sometimes (especially at the end, when the document was already quite big) problems with lost connections that caused loss of some changes. I didn't experienced this before with smaller documents so I assume that either Google Docs Writer is not yet capable of handling long documents having pretty nasty HTML code inside (see the point about the code listing below ) or there had been connection problems caused by server problems. So I guess if I am about to write another similar post I might want to try a desktop application such as OpenOffice (with Sun Weblog Publisher extension) or I might want to separate the a bigger topic into several smaller posts (which would probably the best). I shouldn't use the Styles "Header 1" or "Header 2" from Google Docs as they let to too big headlines in the blog po...

Have you ever considered mirroring/synchronizing your important files from your Mac to your Linux machine to decrease the risk of data loss because of a hardware crash? One very effective way to do this is using two open source tools available on your Mac and your Linux machine called rsync and ssh. This document will lead through the necessary steps. The main reason for this document was to have a reference for myself as it wasn't trivial. Maybe it can be helpful for others. As a precondition, it is assumed, that you have two computers that are connected via a network. I am using a Macbook with Mac OS X 10.4 Tiger and an Ubuntu PC with Ubuntu 7.10 Gutsy connected via a WLAN where I have verified all the steps. Some of the steps described are Mac / Ubuntu specific. Most information should be valid for other operating systems where ssh and rsync can be installed (e.g. other Linux distributions) but you might check out the distribution specifics if something should not work. ...