Linux Configurations

In this page

  1. Change time zone
  2. Change date format
  3. GRUB
  4. cron jobs
  5. Configure the start menu
  6. Release 'Alt' key
  7. Configure thumbnails in tumbler

1. Change time zone

Time Zone

This command changes the current time zone used by the computer. Nothing big, typical thing to use on a laptop when on travel.

$ sudo dpkg-reconfigure tzdata

2. Change date format

Date Format

To impose a different date format, the best option is to redefine a new value for the LC_TIME environement variable. To see the locale variables type:

$ locale

My initial configuration had LC_TIME="en_US.UTF-8", which gives the date in the MM/DD/YYYY format. I want DD/MM/YYYY, instead. Either painstakingly create a new locale file (see how to do that here) or just choose a locale that fits the bill. To keep names in English, yet inverse day an month, the us_GB locale is fine. To set this locale (or the newly created one) for the date:

  1. Edit the /etc/environment file (i.e. sudo nano /etc/environement);
  2. add (or change) the line LC_TIME="en_GB.UTF-8";
  3. Reboot.


To see the grub menu during start up

$ sudo nano /etc/default/grub

and comment (with #) the GRUB_HIDDEN_TIMEOUT lines. Then run

$ sudo update-grub

4. cron jobs

Basics of cron jobs

The basic operations of cron jobs are:

$ crontab -e                     # Edit the cron table
$ crontab [-u username] -l       # List jobs
$ crontab -r -u username         # Remove all jobs from a user

cron syntax

The syntax of a cron tab entry is below. Numbers may be replaced by "*" to mean any number. For weekdays, "0" and "7" mean Sunday.

<MM(0-59)> <HH(0-23)> <day(0-31)> <mon(0-12)> <weekday(0-7)> /path/to/command arg1 arg2 ...

5 0 * * * /path/to/dosomething      # Do something every day at 12:05 am
0 22 * * 1-5 /path/to/dosomething   # Do something every weekday at 10 pm

5. Configure the start menu

  • Go to Start > Settings > Main Menu
  • Add, remove, and change items as you see fit.

6. Release 'Alt' key

In xfce, the 'Alt' key is combined with the left mouse click to allow to move windows around. This is quite annoying as many applications use the same combination for important stuff. For instance, Inkscape utilizes this "alt-left click" combination to browse the selection over superposed objects. I have no use for the move window feature. That is how you can disable the 'Alt' key capture in xfce:

  1. Start menu > Settings > Settings Editor;
  2. Click on "wfwm4" on the left panel;
  3. If necessary expand "General" on the right panel;
  4. Double click on "easy_click" and erase the value 'Alt'.

7. Configure thumbnails in tumbler

For me, thumbnails are useful for images and that is pretty much it. To disable thumbnails for pdf, odf, videos, etc, edit the file /etc/xdg/tumbler/tumbler.rc and set


for types that you do not want a thumbnail. Once that is done, erase the home .thumbnails folder

$ rm -r ~/.thumbnails

and refresh (F5) the screen in thunar.