Linux etc. » Linux

How to connect to kclad (the KCL Active Directory domain)

Marianne — Tue, 30 Aug 2011 10:40:23 +0000

I followed these instructions (I did not get any errors).

sudo aptitude install likewise-open5

Connect:

sudo domainjoin-cli join kclad.ds.kcl.ac.uk LOGIN

Reboot.
Add the line winbind use default domain = yes to the file /etc/samba/lwiauthd.conf
Reboot.
Check if you are connected:

sudo domainjoin-cli query

I now seem to be connected whenever I am on the KCL network.
Leave:

sudo domainjoin-cli leave

(I don’t explicitly leave. It disconnects when I disconnect from the network.)

Find more network printers from the Ubuntu command line

Marianne — Fri, 19 Aug 2011 14:21:54 +0000

Some of the network printers at work do not show up when I try to find them via the Ubuntu GUI System -> Administration -> Printing but I can find them via the command hp-probe. Here at work the list returned by hp-probe is long and I know the names I’m looking for start with “printer0″ so I do

hp-probe -bnet | grep printer0

This returns lines that contain a URI like this

hp:/net/HP_LaserJet_P3005?ip=159.92.99.39

Copy that and go back to the GUI where you paste it under “Enter device URI”

How to get Emacs key bindings in Ubuntu

Marianne — Tue, 16 Feb 2010 12:59:45 +0000

To get the Emacs key bindings (especially, Ctrl-a to go to beginning of line, Ctrl-e to end of line) systemwide, e.g. in Firefox, you use:

gconf-editor

and change the setting desktop → gnome → interface → gtk_key_theme from “Default” to “Emacs”.

Disable pop-up system notification messages in Ubuntu

Marianne — Thu, 11 Jun 2009 08:13:45 +0000

I found the little pop-ups really annoying that show up when I get an icon in the system tray anyway, such as for available software updates.

sudo chmod -x /usr/lib/notification-daemon/notification-daemon

Installing Digikam with fewer dependencies in Xubuntu/ Ubuntu Intrepid

Marianne — Thu, 05 Feb 2009 11:42:49 +0000

If you do

sudo aptitude install digikam

on Intrepid, you will see that aptitude would install loads of KDE packages (Dolphin and Konqueror, yikes). Apparently, this is because aptitude now by default also installs recommended packages as “dependencies”. To avoid this, use the -R flag to aptitude (see also man aptitude):

sudo aptitude install -R digikam

If you prefer Synaptic for the GUI, there is a global option there under Preferences, in the General tab.

Addendum

One issue is that you will not be able to use the Flickr upload plugin without Konqueror, as this version of Digikam uses Konqueror to authenticate you on Flickr. A workaround is to get the lateste KDE4 version of Digikam, which you can do by adding the following four repositories to /etc/apt/sources.list:

deb http://ppa.launchpad.net/digikam-experimental/ppa/ubuntu intrepid main
deb-src http://ppa.launchpad.net/digikam-experimental/ppa/ubuntu intrepid main
deb http://ppa.launchpad.net/kubuntu-experimental/ppa/ubuntu intrepid main
deb-src http://ppa.launchpad.net/kubuntu-experimental/ppa/ubuntu intrepid main

You’ll also have to add the key for each repository using (substitute key number for “9999″):

gpg --keyserver subkeys.pgp.net --recv-key 9999
gpg -a --export 9999 | sudo apt-key add -

Works fine here so far, use at your own risk.

Edimax EW-7318USg and switch to wicd

Marianne — Sun, 11 Jan 2009 18:27:25 +0000

I’ve just bought the Edimax EW-7318USg wireless USB dongle, mainly to use it in corners of the house where the wireless signal is weak. It works fine and does seem to boost the signal.

With network-manager, I found no way to quickly switch between the built-in wireless card and the Edimax. I installed wicd, which uninstalls network-manager if you install it via aptitude (you have to add the repository first, see the wicd website). I like it so far. It seems more transparent in what it does than network-manager. You can manually enter an interface to use for wired or wireless. The Edimax shows up as “wlan0″, if I enter that, it connects via that, else, use the default “ath0″.

It seems I can also quickly put the Edimax into monitor mode via airmon-ng, but I haven’t done anything but watch it collect some packets in wireshark so far.

Running X apps (like zenity) from crontab (solving “cannot open display” problem)

Marianne — Fri, 02 Jan 2009 18:42:00 +0000

I’ve written a small script that checks whether I have queued mail and that displays a notification icon via “zenity –notification” in case I do. I wanted to run it using ~/.crontab but it wouldn’t run. First, I got error messages from the cron daemon that looked like this:

(zenity:22981): Gtk-WARNING **: cannot open display:

Sure, I hadn’t specified a display. So I tried setting the DISPLAY explicitly in my ~/.crontab:

* * * * export DISPLAY=:0.0 && /path/to/checklog

but then I got:

No protocol specified

(zenity:24101): Gtk-WARNING **: cannot open display: :0

The same happened when I tried running other X apps, like audacious. A line in ~/.crontab like this:

* * * * * DISPLAY=:0 /usr/bin/audacious

resulted in errors like this:

No protocol specified
/usr/bin/audacious: Unable to open display, exiting.

It turns out I needed to set, in my ~/.bashrc:

xhost local:mpromber > /dev/null

to allow crontab access to my X display. It now works, either using “export DISPLAY=:0.0″ in the ~/.crontab, or alternatively just using

zenity --notification --display=:0.0

in the script that checks for queued mail.

Ubuntu/ Linux: How to permanently turn off the annoying system bell (beep)

Marianne — Thu, 04 Dec 2008 18:27:48 +0000

You know what I mean … that loud loud beep that almost knocks you out whenever you type a non-available keyboard shortcut in Emacs.

For immediate relief (this will not persist through a reboot):

sudo modprobe -r pcspkr

For permanent relief, edit the file /etc/modprobe.d/blacklist and add the line:

blacklist pcspkr

Addendum

On my Lenovo Thinkpad X41, there was still an annoying loud beep whenever I plugged in or unplugged the AC power cord. I had to disable this in the BIOS.

“trash-cli” lets you move files to the trash from the command line (and shell scripts)

Marianne — Fri, 28 Nov 2008 22:09:38 +0000

I know hardcore Linuxers use rm for everything and think the trash on a computer is for babies who also like such poo-poo things like the mouse and GUIs. However, I’ve just deleted one too many files using rm from a shell script, especially since I like doing rm -rf on directories … confirming every single file is just too tedious. So I googled some and found the best of both worlds: trash-cli lets you move items to the trash can from the command line or shell scripts. You use it simply like so:

trash somefile

Unlike just moving files to wherever you trash folder is using mv, trash-cli does all the nice trashy things like keeping information that will let you easily restore the file (which … ahem … you of course do from the trash can GUI). On Ubuntu, it’s easy to get trash-cli via synaptic:

sudo aptitude install trash-cli

Now, if there only were a way to rename the trash can to “trash” or at least “rubbish” instead of the idiotic “wastebasket” that my Xubuntu with GB locale insists on …

How to add a custom welcome message to your Xubuntu or Ubuntu login screen

Marianne — Fri, 28 Nov 2008 12:53:34 +0000

I like the graphical login screen on my laptop to display my e-mail address. In case I lose the laptop and an honest person finds it, they should at least have the possibility to return it.

In the latest versions of Ubuntu or Xubuntu, you can change the welcome message via the settings menu for “Login Window” (or, at a command line, type “gksudo gdmsetup”). Go to the “local” tab.

However, the custom welcome message is not displayed for a lot of (possibly most or all of) the themes, if you want a themed login window. My guess is that this is because these themes do not display a welcome message at all, period. To work around this, you can manually edit the .xml file of the theme you wish to use. Let’s assume you want to use the “Human” theme for your login screen. Pick that in the gdm setup window. Set your custom welcome message. Now, go to /usr/share/gdm/themes. You will see that this contains folders named after the different themes. You want to change the “Human” theme, so go to that folder. Now, using sudo, edit the file Human.xml. You will see that it contains xml markup, which is similar to hmtl. Add a section that looks like the following (I don’t think it matters where you add it. I added mine after the “ubuntu logo” section and it works fine):

Of course, you can change the position, color and font; this should be easy to figure out. Save the file. Next time you log out, you will see the custom welcome message that you have defined in the GUI for the gdm settings on your login screen.