After installing Lubuntu 16.10 on my Lenovo Y510P, the key binding for volume control (Fn + Left/Right) were not working.

I found out that all key bindings can be easily configured using the XML configuration file ~/.config/openbox/lubuntu-rc.xml.

The default commands were configured as follows:

When executing these commands on the console (lxterminal), I received the following error message:

It appeared that the simple channel name was wrong.

The problem could easily be fixed by manually selecting the first sound card via -c 1 (the option -q serves to suppress any standard output):

The modified part of the configuration files looks as follows. Note: The X server needs to be restarted for the changes to take effect!

After installing Dropbox on a fresh Lubuntu 16.10, I was missing the Dropbox icon in my task bar.

From several posts, I learnt that installing the package libappindicator1 as follows should help:

Alas,  the icon was still missing.

Finally, I found the a post that suggested to set the environment variable XDG_CURRENT_DESKTOP to Unity:

After verifying that this worked, I modified the corresponding desktop entry that corresponds to Dropbox (For a full list, see Start menu -> Preferences -> Default applications for LXSession). The entry is located in ~/.config/autostart on my system. I copied the file Dropbox.desktop to Dropbox-custom.desktop and set the Exec line to the following content.

Afterwards, I disabled the option Start Dropbox on system startup in the Dropbox preferences – otherwise, Dropbox would override the .desktop entry.

Credit: Thanks for idobrinescu, who proposed this fix for Elementary OS Freya.

I regularly have to reduce the size of digital images. To automatize this, I created a little Bash script, which also considers the orientation (landscape/portrait) of the image:

The actual conversion is done with convert, which is part of the ImageMagick suite (for installation instructions, see here).

The option -strip removes all EXIF metadata during conversion and the prefix jpg: ensures that the correct file format is used for the new file.

Edit (2014-11-17): Fix loop condition to cope with file names that contain whitespaces and also to also match JPEG, jpeg,… Thanks, Paul Pell!

This is a short description how to produce a Video DVD from a video file under Linux.

The first step is to convert your movie file from the original format to MPEG-2:

Depending on your TV, you have to choose between PAL and NTSC and between Video CD, Super Video CD, and Video DVD (e.g., ntsc-vcd, ntsc-svcd, ntsc-dvd,…). The option -vb sets the target video bitrate. 8000kbit/s is a guess that worked for me. (Note: avonv is the successor of ffmpeg)

From the MPEG-2 file, you now produce a file structure that is suitable for a Video CD/DVD using the appropriate command below. dvdauthor is known to have problems selecting the video format using the option -v, so the environment variable VIDEO_FORMAT should be used instead

Then, you create a so-called titleset for your CD/DVD with:

Now you are ready to burn your CD/DVD. Open k3b (or another burning tool) and choose “New Video DVD project” (or similar) and copy VIDEO_TS and AUDIO_TS into the root of the project folder.

Acknowledgments

Main ideas stem from here.

Here are some ways to calculate an MD5 and SHA1 sum of a string.

In Bash

The switch -e enables the interpretation of escape sequences and \c (‘End of Text’) suppresses any further output.

In MySQL

In PHP5

 

This post describes how to adapt the size of the Grub splash screen and the virtual terminal on Debian.

In the following, I will set both to the size of 1280 x 1024 pixels. This may not suit your installation. To be sure, install the tool hwinfo and check the available configurations:

Grub splash scren

Open /etc/default/grub (as root) and add/modify the following lines:

Afterwards, update the grub configuration and reboot:

Now, the Grub splash screen appears larger, but the virtual console of Debian is still quite tiny.

Debian virtual console

For increasing the size of Debian’s virtual terminal, open /etc/default/grub, again and add the following line:

Further Reading

If this solution did not work for you, you may try other suggestions from this stackoverflow thread.

This article covers additional dependencies that are required to build KiCad on Ubuntu.

For general instructions on how to install KiCad see here: http://www.kicad-pcb.org/display/DEV/Building+KiCad+on+Linux .

Even though we run apt-get build-dep kicad during the setup, some essential libraries are missing that are reflected in the following command:

The dependencies that apt-get build-dep kicad installed are:

 

 

It can be very fast to safely delete a drive using encryption. The idea is basically to encrypt the whole disk and afterwards to overwrite it with zeros. In this article, I use LUKS, which already ships with Ubuntu 14.04. This procedure may be quicker and more reliable than “copy-based” methods if your CPU supports crypto commands.

First, replace all partitions that should be safely deleted with one large unformatted partition. I assume that this partition is called /dev/sda1 . Afterwards, setup LUKS on the unformatted partition. The password may be a really simple one.

Now, open the encrypted volume, entering the same password:

Afterwards, you start writing zeros into the encrypted partition, which will produce more or less random data on the disk:

 

The Java plugin for Firefox is activated if Firefox finds a symlink to libnpjp2.so in its plugins folder.

  1. Locate the plugins directory of Firefox. You may either use the per-profile or the global directory. In my case these are
  2. Locate the path to your JRE’s browser plugin:
  3. Remove any existing (links to) Java plugins from the plugins folders.
  4. Create a symbolic link to the plugin:
  5. Restart Firefox and verify that the plugin is recognized by opening about:plugins .

References

  • [1] Original instructions

I like to have system messages (such as those by apt-get) to be in their original language – English – while the rest of my localization should be for German. In KDE, this can configured in System Settings -> Locale or with

But even after selecting “American English” as my favorite language, the results of apt-get remained in German, probably because these settings only affect KDE applications. Only after changing the LC_MESSAGES locale property to POSIX, these messages appeared in English.

The changed locale is reflected by the locale command after the next restart: