Operation Manual

Uninstalling Software
If you decide you no longer want a piece of software, apt-get also includes a remove command that cleanly uninstalls the
package along with any dependencies which are no longer required. When you’re using a smaller SD card with the Pi, the ability
to try out software and quickly remove it is extremely useful.
To remove thrust, simply open the terminal and type the following command:
sudo apt-get remove thrust
The remove command has a more powerful brother in the form of the purge command. Like remove, the purge command
gets rid of software you no longer require. Where remove leaves the software’s configuration files intact, however, purge
removes everything. If you’ve got yourself into a mess customising a particular package and it no longer works, purge is the
command to use. For example, to purge thrust, you would just type this:
sudo apt-get purge thrust
Upgrading Software
In addition to installing and uninstalling packages, apt can be used to keep them up to date. Upgrading a package through apt
ensures that you’ve received the latest updates, bug fixes and security patches.
Before trying to upgrade a package, make sure the apt cache is as fresh as possible by running an update:
sudo apt-get update
When upgrading software, you have two choices: you can upgrade everything on the system at once or upgrade individual
programs. If you just want to keep your distribution updated, the former is achieved by typing the following:
sudo apt-get upgrade
To upgrade an individual package, simply tell apt to install it again. For example, to install a thrust upgrade, you would type
this:
sudo apt-get install thrust
If the package is already installed, apt will treat it as an in-place upgrade. If you’re already running the latest version available,
apt will simply tell you it cannot upgrade the software and exit.
For more information on package management with apt—in particular, how certain packages can be “kept back” and excluded from upgrades—type