Libre Things

A friend of mine has a PC with Windows XP / Ubuntu in dual boot. After the Lucid upgrade, Windox fails to boot (strange lines on the screen after Grub...).

TestDisk saved us:

sudo aptitude install testdisk
sudo testdisk

1. Choose [ Create ] Create a new log file
2. Choose windows physical disk, then [Proceed ]
3. Choose [ Continue ] Continue even if there are hidden data
4. Choose [Intel ] Intel/PC partition
5. [ Advanced ] Filesystem Utils
6. On Windows XP partition, boot sector is generally bad or non identical to backup sector (Sectors are not identical.).
7. Choose [ Backup BS ] to copy the backup sector to the master sector.
8. After that, quit, reboot and test.

Sources:

• http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step#NTFS_Boot_sector_recovery
• http://ubuntuforums.org/showthread.php?p=9263959

With the last Ubuntu Lucid 10.04 come a new graphical module: KMS or Kernel-based Mode-Setting.

If you have performance problems in some games like Quake 3 or TCE / Enemy Territory, try to disable KMS. The problem can also be with the mouse pointer (slowness, lag, delay or inacuracy).

Grub 2

Add nomodeset in /etc/default/grub then issue the command update-grub.

vi /etc/default/grub
GRUB_CMDLINE_LINUX="nomodeset"
update-grub

Grub 1

Add nomodeset at the end of the # kopt line, then issue command update-grub.

vi /boot/grub/menu.lst
# kopt=root=/dev/sda1 ro nomodeset
update-grub

Someone also told me that disabling KMS solved his Firefox javascript speed problem in Yahoo Mail.

Audio CD copy is actually not possible with Brasero on Ubuntu Lucid. All details in the bug report.

As a workaround, you must install cdrdao version 1.2.3, which is not yet available as a package.

To install it, you can use CheckInstall which is a bit cleaner than the old make install:

tar -xjvf cdrdao-1.2.3.tar.bz2
cd cdrdao-1.2.3/
./configure
make
sudo checkinstall make install

Note: the make command can fail because of missing dev packages you'll have to install.

CheckInstall builds and installs a nice Debian package.

You can also use cdrdao directly. ps axf shows us the command Brasero is using:

cdrdao read-cd --device /dev/sr0 --read-raw --datafile /home/dooblem/brasero.toc.bin -v 2 /home/dooblem/brasero.toc

Here we go!

Links :

• http://packages.debian.org/lenny/checkinstall
• http://en.wikipedia.org/wiki/CheckInstall
• Audio CD Backup/Archive

If you like beautiful images, you certainly knows Featured Pictures on Wikimedia Commons project.

Magnus created a small tool to see all the last selected features pictures : Catfood.

Catfood works for any Wikimedia Commons category.

The RSS feed:

http://toolserver.org/~magnus/catfood.php?category=Featured_pictures_on_Wikimedia_Commons

Links:

• Catfood and source code
• Magnus' toys'n'tools

Here is a small C program I wrote some years ago: Clictap. It's very convenient and I'm still using it to watch my movies.

It makes use of Xlib and Xtest libraries to replace your mouse buttons by keyboard keys.

I made a small Debian package a few days ago:

clictap_0.6-1_i386.deb

soon included in the official repositories ?

Configuration file example including profiles for totem, xmms, rhythmbox and mplayer:

# ClicTap configuration file
# You can copy this example to ~/.clictap.conf

# When this key is pressed, Clictap will ungrab your mouse and quit
# Examples :
# quit_key q
# quit_key ctrl+q
quit_key q

# Profile used by default
default_profile mplayer

# List of profiles
# For each profile, a set of buttons to keys translations is given,
# each translation on a separate line.
# For a translation, the first field is the set of buttons,
# the second is the set of keys.
# Buttons are specified by their numbers.
# Keys are specified by their KeySym (Key Symbols).
# To know the button numbers and KeySyms, use the xev program to test X events.
# Example :
#
# profile foo
# 	1   a
# 	2   b+c
# 	3+1 space
# 	3+2 Control_L+d

profile totem
	1 b
	2 p
	3 n
	4 Up
	5 Down

profile xmms
	1 w
	2 c
	3 b
	4 Up
	5 Down

profile rhythmbox
	1 Alt_L+Left
	2 Control_L+space
	3 Alt_L+Right
	4 Control_L+Up
	5 Control_L+Down

profile mplayer
	1 Left
	2 space
	3 Right
	4 asterisk
	5 KP_Divide

profile mplayersub
	1 x
	2 space
	3 z
	4 asterisk
	5 KP_Divide

profile test
	1 XF86AudioLowerVolume
	2 space
	3 z
	4 asterisk
	5 KP_Divide

The well known way to remove a service from system boot under Debian / Ubuntu, without removing the package:

update-rc.d -f mysql remove

This command removes all /etc/rc*/*mysql* symbolic links. At next boot, the service is not started.

Problem: when you update the mysql package (aptitude update), symlinks are created again.

Solution: in the last update-rc.d versions, there are disable / enable commands:

update-rc.d mysql disable

Useful if like me you only start apache or mysql some times for Web development. Also useful if you share files with Samba and only want to start the daemon occasionaly.

Note: update-rc.d --help tells us that The disable|enable API is not stable and might change in the future.

References:

• http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=546580
• http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=67095
• man update-rc.d

In some modern distributions like Ubuntu, there are preconfigured user directories like Desktop, Download, Documents, Images, Music, Vidéos.

You can remove some of the directories you don't use, or rename some of them.

If you change their name, you can set their new place in your ~/.config/user-dirs.dirs file:

# This file is written by xdg-user-dirs-update
# If you want to change or add directories, just edit the line you're
# interested in. All local changes will be retained on the next run
# Format is XDG_xxx_DIR="$HOME/yyy", where yyy is a shell-escaped
# homedir-relative path, or XDG_xxx_DIR="/yyy", where /yyy is an
# absolute path. No other format is supported.
# 
XDG_DESKTOP_DIR="$HOME/Bureau"
XDG_DOWNLOAD_DIR="$HOME/telech"
XDG_TEMPLATES_DIR="$HOME/"
XDG_PUBLICSHARE_DIR="$HOME/public"
XDG_DOCUMENTS_DIR="$HOME/docs"
XDG_MUSIC_DIR="$HOME/zic"
XDG_PICTURES_DIR="$HOME/images"
XDG_VIDEOS_DIR="$HOME/cine"

Then restarting Nautilus should be sufficient. Otherwise restart your Gnome session.

References:

• http://www.freedesktop.org/wiki/Software/xdg-user-dirs
• aptitude show xdg-user-dirs

XSplash is new in Ubuntu Karmic. If you don't like this ugly screen like me, here is how to disable it.

The dpkg -l | grep xsplash command tells you that two package are responsible for this horrible screen: xsplash and ubuntu-xsplash-artwork. To remove them, you also have to remove the ubuntu-desktop package. That is not recommended if you don't want to miss something in the next Ubuntu upgrade.

Here it is:

sudo rm /etc/dbus-1/system.d/xsplash.conf
sudo touch /etc/dbus-1/system.d/xsplash.conf

We remove the file and create an empty one. Why ? Because if we just delete the file it will be created back again during the next update. If you create an empty file in place, the next update will ask you what to do with the file.

Et voila, restart and enjoy the "visual peace".

Link:

• Thing origin's

See also:

• [Ubuntu Karmic] Disable USplash
• Display Ubuntu boot commands

Before doing anything: backup your sensible data!

To extend a partition and it's filesystem, you have to:

1. Extend the partition
2. Extend the filesystem

To shrink a partition and it's filesystem, you have to:

1. Shrink the filesystem
2. Shrink the partition

For an ext3 partition, simply use parted:

parted /dev/sdx
print
resize N

Parted doesn't support ext4 (yet?). For an ext4 partition or if parted refuses to resize your ext3 partition (Error: File system has an incompatible feature enabled.), use resize2fs:

To extend:

cfdisk /dev/sdx
# delete the partition and create it again with the desired size
resize2fs /dev/sdxY

Without giving any size, resize2fs extends the filesystem to the partition's size.

To shrink, it's almost as simple:

# example if you want a 10G partition
# resize filesystem with a size smaller than the desired size
resize2fs /dev/sdxY 9G
cfdisk /dev/sdx
# delete the partition and create it again with the desired size
# (a little bigger than the filesystem!!)
# then launch resize2fs again
resize2fs /dev/sdxY

Doing so we get the good partition size without loosing any space.

Notes:

• If your partition is over LVM, you can use the lvresize or lvextend or lvreduce commands to resize the partition, instead of deleting/creating the partition with cfdisk.
• The method also works for other filesystems like NTFS. For NTFS, you will use the ntfsresize command, or parted if it works.

Links :

• man resize2fs
• http://www.gnu.org/software/parted/manual/parted.html
• http://ext4.wiki.kernel.org/
• http://ext4.wiki.kernel.org/index.php/Frequently_Asked_Questions#How_to_online_resize_the_Ext4_filesystem.3F

Looking for a simple and lightweight terminal, I found urxvt.

xvt and rxvt don't support Unicode characters. You have to use urxvt :

aptitude install rxvt-unicode

Not that I find xterm too slow for my use. My "geek curiosity" took over. I don't like terminal tabs but instead open plenty of different terminal windows. urxvt could certainly do the job.

Then you can customize urxvt using the ~/.Xdefaults file :

vi ~/.Xdefaults
Rxvt*scrollBar: False
Rxvt*background: black
Rxvt*foreground: white
Rxvt*geometry: 110x35

The geometry I use allow me to open 4 terminal windows in my screen.

Note: you can also put parameters in ~/.Xresources but you'll have to restart X or use the xrdb -merge ~/.Xresources command to load parameters.

I also suggest you the use of a keyboard shortcut to start your terminals. In Gnome :

1. Set your default terminal in System > Preferences > Prefered Applications
2. Then in System > Preferences > Keyboard Shortcuts, set the Start Terminal entry. I use Alt+X.

References :

• LANG=C aptitude search ~dterminal | grep -i "terminal\|emulator" | less
• http://fr.wikipedia.org/wiki/Urxvt
• http://software.schmorp.de/pkg/rxvt-unicode.html
• http://www.debian-administration.org/article/Customizing_your_xterm