How to set/get default values for configuration keys

It looks like dconf (the command) doesn’t read values of keys that haven’t been explicitly set by the user.

jani@saegusa:~$ dconf read /org/gnome/desktop/session/idle-delay
jani@saegusa:~$ 

So how do I get the value of idle-delay whether or not it’s user-set?

By using gsettings instead of dconf:

jani@saegusa:~$ gsettings get org.gnome.desktop.session idle-delay
uint32 600

Note that setting the value to what is default for the key isn’t the same as resetting the key:

jani@saegusa:~$ dconf write /org/gnome/desktop/session/idle-delay 'uint32 600'
jani@saegusa:~$ dconf read /org/gnome/desktop/session/idle-delay
uint32 600

You see, now even according to dconf the key is set even though it just holds the default value.

To actually reset the dconf key, you use its reset command:

jani@saegusa:~$ dconf reset /org/gnome/desktop/session/idle-delay
jani@saegusa:~$ dconf read /org/gnome/desktop/session/idle-delay
jani@saegusa:~$ gsettings get org.gnome.desktop.session idle-delay
uint32 600

BitlBee

20:19 <@uusijani> no
20:19 <@root> Did I ask you something?
20:19 <@uusijani> no
20:19 <@root> Did I ask you something?
20:19 <@uusijani> yes
20:19 <@root> Did I ask you something?
20:19 <@uusijani> yes
20:19 <@root> Did I ask you something?

BitlBee: Y U NO YES NOTHING

Booting Ubuntu’s Minimal CD iso from Grub2

Today I got me a used Acer Aspire One ZG5. It came with preinstalled Ubuntu, but also with the previous owner’s data that they obviously wished to be wiped first.

The ZG5 doesn’t have an optical drive, and I don’t have any thumbdrives bigger than 256 MB, so reinstalling took a bit of creativity.

The obvious choice might have been to get an installation iso smaller than 256 MB, stick it to a thumbdrive and proceed from there. But I figured, I already have Grub and schtuff from the previous installation on the disk, so why not make use of it?

The Boot & Install Ubuntu from the Grub Rescue Prompt HOWTO on Ubuntu Forums looked like the way to go, but I wanted to use the toram option to make unmounting of the iso work. As the ZG5 (by default) only has 512 MB of memory, cramming an entire CD’s worth of data into it wouldn’t be possible, so I grabbed the minimal CD image of Precise, which currently is 24,1 MB. To do this I recovery-booted the pre-existing installation and used wget to download the image into /root.

I then rebooted and went to the Grub commandline. Just as in the Howto, I set the Grub modules path, loaded necessary modules (no Microsoft filesystems needed, the old / was ext2), set the loopback and root.

set prefix=(hd0,1)/boot/grub
insmod linux
insmod loopback
insmod iso9660
loopback loop (hd0,1)/root/mini.iso
set root=(loop)

Next was the linux commandline. The mini CD doesn’t have casper and location of files differs slightly from the Live CD. I also added the toram parameter:

linux /linux iso-scan/filename=/root/mini.iso noprompt noeject toram
initrd /initrd.gz

Then just

boot

Apport opens Opera instead of default browser

I’m titling this the way it seemed to me back when I was wondering what was going on. In fact the issue is that system problems are reported with root privileges, and Opera had hijacked the system-level default browser position (my normal account still used my choice). You can see which browser is the superuser default by issuing

$ sudo xdg-open 'http://www.google.com'

You can configure the default with

$ sudo update-alternatives --config gnome-www-browser
$ sudo update-alternatives --config x-www-browser