Package Management & Program Installation

Question 1

Why do you need a package manager?

Answer 1

A Package Manager is used to simplify the installation and the removal of programs.

If one package requires another one, it is automatically installed as well.

Typically, package managers can handle updates and system upgrades, too.

=> a package manager presents a complete, centralised installation system

Question 2

Which package form does the Debian package manager accept?

Answer 2

.deb

Question 3

Which package manager uses ubuntu?

Answer 3

Uses the debian package management system

Question 4

What is contained in a .deb package?

Answer 4

Such a package is, in principle, a compressed archive containing the program in binary form along with special control files that are interpreted by the package manager. These files contain information about the package, including its dependencies.

Question 5

What’s the command name for the Debian package manager?

Answer 5

dpkg

Question 6

What does APT stand for?

Answer 6

Advanced Packaging Tool

Question 7

What is APT? What does it do?

Answer 7

The Advanced Packaging Tool (APT) is a frontend to dpkg. It handles package retrieval and package querying, as well as the resolution of dependencies. Internally, APT calls “dpkg” to install or remove packages.

Question 8

Name a console-based package manager

Answer 8

aptitude

Question 9

Name a GUI package manager

Answer 9

Synaptics

Question 10

Which tool is the most convenient for Ubuntu home users for their software installation?

Answer 10

Ubuntu Software Center

Question 11

From which sources can software be installed?

Answer 11

any removable (CD, USB) or non-removable media (internet)

Question 12

How can you search within the package database?

Answer 12

APT maintains a package database, where meta information (name, dependencies and description) is stored. The option “search” allows to search within the database

Question 13

How do you keep your package database up-to-date?

Answer 13

If you are connected to the Internet:

The tool “apt-get” is responsible for updating the database.

Question 14

What could happen if your database is not up-to-date?

Answer 14

Program downloads may fail due to outdated information

Question 15

In which 2 ways can programs be installed?

Answer 15

• if locally available via the debian package using dpkg -I

- if found via apt-cache, it can be installed using apt-get (download from the internet or a CD-Rom)

Question 16

Which two options do you have if you want to remove a program?

Answer 16

You can either leave the configuration files in place (remove) or by deleting the configuration files as well (purge).

Both methods are provided and handled by tools already discussed, apt-get and dpkg

Question 17

How does the updating process work?

Answer 17

Whenever a new version of a program is released, the local package database is updated. BUT no installation is performed. In order to install those updates, the command apt-get upgrade installs the new version of all available packages.

Question 18

What can you do if there is no package available for a required program?

Answer 18

Build the program from source. The build process, involving the compilation of the source files, creates a binary, runable program.

Question 19

How does the compiling a program from source work?

Answer 19

At first, some necessary prerequisites, for instance libraries needed by the program to build, have to be installed. This can be done either via the package manager or by building them from source as well. Then, the source code has to be downloaded and unpacked to a local directory. Afterwards, the actual compilation process can be started and after completion, the program can be installed and/or executed.

Question 20

How can you get a program’s source code?

Answer 20

Download from the internet:

• as a compressed archive directly from the homepage
• repositories for version control, like Subversion (SVN), git or Mercurial (hg).
• websites to look for open source projects are github.com and sourceforge.net

Question 21

Where can you find information on how to build the program?

Answer 21

INSTALL, README files

Question 22

What does tar stand for?

Answer 22

The name “tar” is short for “tape archive” and comes out of historic reasons when backups of files were performed on tapes.

Question 23

What are patches?

Answer 23

Fixes to errors or new features not made by the original author.