Omega, door Jack McDevitt

“The logical heir to Isaac Asimov and Arthur C. Clarke,” schrijft Stephen King op de kaft van Omega. Daar klopt weinig van: McDevitt heeft een heel eigen stijl. Zijn verhalen hebben realistische karakters en zijn drama is ongeforceerd. Sommige schrijvers introduceren personages met tegengestelde karakters om conflicten te creëren. Dat doet vaak erg geforceerd aan. James P. Hogan schreef een hele serie zonder kunstmatige conflictdrama en die doet volgens mij (en vele anderen) zeker niet onder voor scifi mét. Sterker nog: geforceerde drama kan me gestolen worden. Clarke deed dit vaak, maar compenseerde met sterke vragen en techniek.

omega

Omega gaat over de zgn. Omega-wolken die door de ruimte bewegen en alles vernietigen met rechte hoeken. Het is een reddings- en ontdekkingsverhaal. Hoewel de idee van een omega onwaarschijnlijk klinkt, is het geen onmogelijkheid en dat is een beetje McDevitts devies: wat niet onmogelijk is, zou best eens waar kunnen zijn.

Enige handwavium in de vorm van faster-than-light-travel maar gezien de verhouding tussen fatsoenlijke drama (namelijk in niet-overheersende hoeveelheden), spanning en filosofie vond ik Omega een geweldig boek om te lezen. Geen wereldschokkende stof tot nadenken maar wel erg fijne scifi.

Echte scifi-films

Veel films die als scifi te boek staan, zijn eigenlijk meer horror of actie en de scifi erin is maar een middel. Hier zijn een paar films waarin de scifi een prominentere plaatst inneemt dan de actie of horror (indien überhaupt aanwezig). Sommige films in de lijst vallen nog steeds onder de categorie ‘rennen en schieten’ maar dat is dan niet waar het verhaal op moet drijven.

De titels linken naar de IMDb en openen in een extern venster. De lijst is een work in progress en in geen bepaalde volgorde.

Update-alternatives in Debian Wheezy – changing the logon wallpaper the right way

Debian Wheezy has a system for keeping one setting sycnronized for multiple applications. It is called the Debian Alternatives System. Is was designed to enable the OS to automatically choose a program where multiple alternatives are available but it also handles artwork like the logon wallpaper.

So I wanted to change the wallpaper for my Lightdm and my personal desktop in Xfce4 to the same picture. I did that using update-alternatives.

Wallpaper set with update-alternatives I downloaded the wallpaper from Wallxite.com; it has the imaginative name of 'fiction-wallpapers-0013'.
Wallpaper set with update-alternatives
I downloaded the wallpaper from Wallxite.com; it has the imaginative name of ‘fiction-wallpapers-0013’.

Wallpapers are stored in /usr/share/images/desktop-base. I downloaded mywallpaper.jpg and copied it to the wallpaper directory:

# cp /home/vorkbaard/mywallpaper.jpg /usr/share/images/desktop-base/

Make it readable for anyone:

chmod 644 /usr/share/images/desktop-base/mywallpaper.jpg

Then I tried to set it as wallpaper with update-alternatives:

update-alternatives --config desktop-background

Update-alternatives showed me all the files in the desktop-base directory except my newly downloaded wallpaper! So I tried to set the file manually:

update-alternatives --set desktop-background /usr/share/images/desktop-base/mywallpaper.jpg 65

(65 being the priority – not really relevant here but Debian needs one. Any numeric value will do.)

Now update-alternatives said my file was not registered. Ok, to register the picture:

update-alternatives --install /usr/share/images/desktop-base/desktop-background desktop-background /usr/share/images/desktop-base/mywallpaper.jpg 65

See if my picture is available for –config:

update-alternatives --display desktop-background

That listed all available (registered) wallpapers, including mine. I set it with

update-alternatives --config desktop-background

…and choosing my wallpaper. The –set option would most probably also have worked now.

Rebooting showed the wallpaper in my profile was alright now but not yet on the logon page. Since I use Lightdm I edited /etc/lightdm/lightdm-gtk-greeter.conf thusly:

background=/usr/share/images/desktop-base/desktop-background

Solved: Debian Wheezy hangs on reboot when network shares are mounted

I have two network shares I mount on my Wheezy laptop via fstab. But when they are mounted my laptop hangs on poweroff of reboot. The cause is that the network part of the system is stopped before the shares are unmounted. The solution is to unmount the shares before the network part is stopped.

The shares I am mounting are Samba shares but I’ve also experienced this with nfs shares. I have two of them; one is mounted on /home/vorkbaard/vorkbaard and the other on /home/vorkbaard/media.

First create a script to unmount the shares and put the script in the designated directory of /etc/init.d/. Let’s call the script unmount_shares.sh. Put this in it:

#!/bin/bash
umount /home/vorkbaard/vorkbaard
umount /home/vorkbaard/media
exit

Make the script executable:

chmod +x /etc/init.d/unmount_shares.sh

Now, I want this script to be executed:
– before the networking is stopped;
– in runlevels 0 (poweroff) and 6 (reboot).

Let’s see which priority the networking has in those runlevels (checkling poweroff for now):

ls /etc/rc0.d/

Networking is the 25th item in the list on my system so I need to run my script with a lower priority, for example 10.

Now that I have the unmount script and I know what priority to give it, I should make symlinks to the appropriate runlevels. I can use update-rc.d for that:

update-rc.d unmount_shares.sh start 10 0 6

‘Start’ here just means: execute the script. 10 is the priority and 0 and 6 the runlevels.

After this my Wheezytop happily powers down or reboots \o/

Make backlight buttons work in Debian Wheezy on a HP EliteBook 8460p

The backlight hardware buttons weren’t working on my HP EliteBook 8460w so I was using

sudo xrandr --output LVDS --brightness 1

and

sudo xrandr --output LVDS --brightness .5

That sort of worked but it only multiplied the gamma values. randr is a software solution – it doesn’t really change the backlight strength.

Here’s how I made my backlight buttons (the hardware buttons on the F9 and F10 keys) work in Debian Wheezy on my laptop.

1. Add contrib and non-free to the source list
2. Do

# aptitude update
# aptitude -r install linux-headers-amd64 fglrx-driver

3. Create an initial Xorg config file:

aticonfig --initial

3. Reboot.

Now I am one (mildly) illuminated guy \o/

Source: https://wiki.debian.org/ATIProprietary#AMD_Catalyst_12.6

/Edit
This breaks some compositing features on my desktop and the fan keeps on all the time. Also it broke Plymouth on my system but that is probably my own fault. For now I’ve removed the proprietary driver. Suggestions on the fan and compositing would be welcome.

/Edit 2
This works for me in Debian Jessie. Haven’t noticed any drawbacks yet.