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Package Management Tools

dpkg is a command line interface to the basic package management functions

in a Debian system. This is the earliest tool provided for the system, and

provides all the direct access to the package manager database as well as the

direct manipulation of the packages to install, upgrade, or remove individual

packages. In this section the use of dpkg to install packages, check on the

status of packages, upgrade packages, check which packages are installed on

the system correctly and which failed to completely install, and removal of the

package will be discussed. Examples of each activity will be provided to make

clear how each of these features can be used on your new system.

While dpkg is the real workhorse of the package management system, the

system maintainer will probably only use it on rare occasions to actually install

packages. The first tool to provide features that allowed the installation of

multiple packages in one pass was dselect. This tool is a full screen interface

that allows browsing and choosing from all of the packages available in an

archives. This section will cover such tasks as selecting an archival method,

updating the available packages database, selecting packages for installation,

dependency management, installation, and configuration. While this tool has

some limitations, there are access methods for every conceivable archives type,

and is often the tool of choice for installing several packages at once.

The major deficit for dselect is that it is incapable of installing the packages

in a preferred order. Sometimes this leads to packages that will not install on

the first pass because some package that it depends upon has not yet been

installed. apt get understands the order requirements of the packages it is

going to install, as well as automatically dealing with the dependencies on the

packages specified. While apt get is primarily a command line interface, it has

many advantages when installing multiple packages, and works as well over

the net as with a local archives. A complete description of how to set up and

use apt get will be presented in the last section of this chapter and will include

a discussion of tasks packages as another way to install multiple packages in a

useful group.