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!

By coincidence I recently found out how to open an Eclipse workspace via drag and drop on Windows.

It is actually a simple trick, but I want to share it anyway:

  1.  Create a link to the eclipse.exe that you want to use (e.g., named EclipseWorkspaceDragAndDrop on your Desktop).
  2. Open the properties of the link (e.g., via Alt+Enter).
  3. Locate the Target input field, whose content should end in eclipse.exe right now.
  4. At the very end of the input field, append -data.
  5. Open the Explorer (or suchlike), navigate to the parent directory of your workspace directory, and drag the workspace directory onto the link (e.g., EclipseWorkspaceDragAndDrop)
  6. Eclipse should startup into the selected workspace without asking you to choose one.

 

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.

PowerPoint is a great tool for creating figures. Recently, I created a number of relatively large figures that considerably exceeded the slide boundary.

However, if you scroll slightly across the borders of the figure (using the mouse wheel), PowerPoint switches to the previous or next slide, which is really annoying.

It seems taht this feature cannot be switched off in PowerPoint 2013, but, thankfully, I found the following pragmatic solution [1]:

  • Open the Master slide view
  • Place some forms (e.g., rectangles) very far outside the slide area in all four directions.
  • Close the Master slide view

References

[1] Microsoft Community: How to stop Powerpoint from jumping to next/previous slide when editing. https://answers.microsoft.com/thread/38c6d159-5667-4aef-b329-5772ae29ce42

When using JUnit for creating unit tests, I have always felt annoyed that Eclipse keeps on suggesting (or even auto-importing) junit.framework.Assert, which is actually a deprecated type but appears first in the list of import suggestions.

To disable this behavior, one has to change the so-called Access Rules for the JUnit library.

To do this:

  1. Right-click you project and select Build Path -> Configure…
  2. Switch to Libraries tab and locate the used junit.jar
  3. Select Access rules and press Edit.
  4. Add a new rule with the rule pattern junit/framework/Assert and set its access level to Forbidden.
  5. Make sure that the rule appears before the junit/framework/* rule, which permits any acccess.

Now, Eclipse should only provide for one import quick fix, when using Assert. Even “Organize Imports” (Ctrl+Shift+O) should automatically find the correct solution now.

Thanks to this Stackoverflow post for hinting me at this solution.

Oftentimes, files that have no ending can be treated as text files. Still, Windows 8.1 kept asking me, which program to use for such files.

The solution is to provide a default program for files without extension – and this can be easily done, even without modifying the registry directly:

  1. Open a priviledges Shell:
    (Windows+Q -> cmd -> Context menu -> Run as administrator
  2. Enter:
  3. Enter:
  4. (Optional) Enter the following to get a nicer default icon for files without extension:

Thanks to this post at Stackoverflow for the solution.

The network emulator Mininet offers VM images for download, which can be imported, e.g., into VirtualBox.

A common problem seems to be that the delivered ovf file (in my case mininet-2.1.0-130919-ubuntu-13.04-server-amd64.ovf) causes an exception when VirtualBox tries to import it: VBOX_E_NOT_SUPPORTED (0x80BB0009).

Even setting the OS manually to Ubuntu (64bit) did not help.

I finally found the solution in this post: You may also create a new virtual machine and select the contained VM disk image mininet-vm-x86_64.vmdk as hard disk.

The utility svnrdump allows you to dump and load Subversion repositories, including the whole revision history.

A typical use case for svnrdump looks like this:

To find out which revisions a particular dump file contains, grep comes in handy: The contained revision numbers are stored in plain text and in increasing order in the dump file.

returns all stored revisions. To find out the first or last contained revision, simply use head and tail:

 

The above error message appeared after I unzipped the downloaded Eclipse using Cygwin (because Windows 8 was unable to handle that long paths).

The reason is that the contained libraries (DLLs) are not executable, which can be easily resolved:

This solution has been proposed on stackoverflow.

Cygwin is a great Unix emulation for Windows. A killer feature, to my mind, is its ability to handle arbitrary long file names (e.g., when moving or deleting files), which is for some ominous reasons still impossible in current versions of Windows.

A very useful command in the Cygwin repository is chere: It adds a context menu entry that allows to start the Cygwin Terminal from the current directory.

Here are the steps to install:

  1. Install Cygwin. See http://cygwin.org/ for details.
  2. In the package selection dialog, select chere, which is located below Shells, for installation.
  3. Open a Cygwin Terminal as Administrator
  4. Type chere -i to install a context menu entry. You may also try chere -h to get more info. Running chere -u uninstalls the context menu entry.
  5. Let’s try it out: Open your file manager and right-click into a folder and select Bash Prompt Here.
  6. A terminal pops up with the current working directory set to the selected folder.

References

This solution and some alternatives are listed in a stackoverflow thread.