Debian and XFCE: Print Screen Key

Print Screen Key

To enable the print screen key, just head on to Application Menu > Settings > Keyboard and click on the Application Shortcuts tab.

Add a new command and in the text box enter in the following:

xfce4-screenshooter -f

Hit Ok, and the next dialogue will require you to enter in the key (or key combination) that will trigger this command (in this case, we will press the 'Prt Scr' key).

References:

• https://wiki.archlinux.org/index.php/Xfce

Debian: Installing gitolite

Tried setting up gitolite in Debian following my earlier guide with CentOS, but it didn't work out as well because there were a few steps missing (Debian doesn't create the gitolite user automatically). These are the modified steps:

1. Install gitolite:

   sudo apt-get install git git-core python-setuptools gitolite

2. Add the gitolite user (this is the user that will host the git repositories and control access):
   

   sudo useradd gitolite

3. As the user who will be administrating the set-up (i.e. someone OTHER than the gitolite user), create a set of ssh keys and move them to where the gitolite user can access them:
   

   ssh-keygencp ~/.ssh/id_rsa.pub /tmp/admin.pub

4. Switch to the gitolite user:
   

   sudo su - gitolite

5. Run the set-up command:
   

   gl-setup /tmp/admin.pub

6. As the user who will be administrating the set-up, clone the repository
   

   git clone gitolite@[ip address]:gitolite-admin.git

You can now add in other keys and set up the configuration of gitolite.

References:

• http://gitolite.com/gitolite/install.html
• http://tipstricks.itmatrix.eu/?p=1693

Debian and XFCE Dual Monitors

Open up a terminal and type in xrandr. This will output the configuration of the currently connected monitors. Identify the names of your monitors (such as HDMI2, LCD1, VGA1, CRT2 or whatever). In this example we have two monitors, HDMI1 and HDMI2.

Now type in the desired layout:

xrandr --output HDMI2 --left-of HDMI1

The monitors should now be showing your desired screen laytout. If not, play around until you have it.

To make this layout permanent, click on the Start menu > Settings > Session and Startup and then click on the Application Autostart tab. Add a new autostart item and then insert the xrandr command into the Command text field. Now if you restart your settings will be automatically loaded!

References

• http://www.linuxquestions.org/questions/showthread.php?p=4658799

Debian: Sound issue

I had a bit of an issue with ALSA and Debian in regards to my sound device not being detected properly. This meant I had to dig around a bit to get it up and running.

Note that with this method may not work nicely with multiple sound cards. Your mileage may vary....

Problem:

Running the command alsamixer in a terminal returned this error message:

cannot load mixer controls: Invalid argument

Trying to restart the ALSA server got me this:

root@localhost:~# /etc/init.d/alsa-utils stop
[....] Shutting down ALSA...warning: 'alsactl store' failed with error message 'alsactl: get_control:250: Cannot read control info '2,0,0,Front Playback Volume,0': In[FAIL argument'...failed.

So there was something wrong with the system configuration or the control.

For reference, this is what my system has configured:

root@localhost:~# head -n 1 /proc/asound/card0/codec*
==> /proc/asound/card0/codec#2 <==
Codec: Realtek ALC887-VD

==> /proc/asound/card0/codec#3 <==
Codec: Intel PantherPoint HDMI

 root@caesar:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC887-VD Analog [ALC887-VD Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 1: ALC887-VD Digital [ALC887-VD Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Explanation of these commands (skip if you want to get to the solution)

The first command reads out the first line (head -n1) of each of the files that match the search pattern (/proc/asound/card0/codec*). This matches two files (codec#2 and codec#3). The /proc/ filesystem is where Linux stores all the files necessary for running the operating system, including detected hardware devices. The first file tells us that the system recognizes the motherboard sound card, and the second files recognizes the HDMI output.

The second command confirms our suspicions, and also let's us know that ALSA detects these devices too (the Realtek and the HDMI devices are found and configured).

Now we know that the problem lies in the ALSA configuration, because everything is detected at this stage.

Solution:

1.  Run the following command and look for your audio device:
   
   

   lspci -v

2. The above step is important because you need to find the line 'Kernel driver in use' associated with your Audio controller (which is outputted by the above line). In my case the kernel was using snd_hda_intel.
3. Now we need to check to ensure the driver is installed. A simple way is to start off writing (DO NOT PRESS ENTER YET!) modprobe snd and then tab complete it (press the <TAB> key twice). This should bring up a list of sound drivers your system knows about. If your driver is not listed you should try to find and install it.
4. Edit /etc/modprobe.d/alsa_base.conf and add the following line (you may need to adjust this to suit your system):
   

   options snd-hda-intel model=generic

5. Now we need to force ALSA to load the new configuration:
   

   alsa force-reload

6. If you can hear sound after running the following command, congratulations!
   

   aplay /usr/share/sounds/alsa/Front_Center.wav

References: 

• http://ubuntuforums.org/showthread.php?t=1578361&p=10182296#post10182296
• http://crunchbang.org/forums/viewtopic.php?id=2310
• https://wiki.debian.org/SoundFAQ