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Chapter 4 ✦ Software Management
Figure 4-1: aptitude’s main display.
3. Aside from the categories shown in Figure 4-1, at times others will appear,
such as
New Packages and Upgradeable Packages. We’re primarily inter-
ested now in the packages that are currently installed, so use the up and
down arrow keys to highlight that category, and press the Enter key. The cate-
gory will expand into a number of subcategories. Each package in Debian is
assigned a particular category, and this listing shows how the results are
often displayed.
4. Now highlight
Editors and press Enter. The next (lower) category level is dis-
played; this is the license level, and it allows you to restrict your listing to a
particular style of license. Packages in the
main archive on this level are
totally free for use, modification, and redistribution. Though you likely don’t
see any on your screen, packages in the
contrib and non-free archives have
other licensing or use restrictions that may require a careful license examina-
tion on your part.
5. Press Enter to expand the
main category. You should now see three packages:
ed, nano, and nvi. These are the only text editors installed on the system by
default. Examine an example line:
i ed 0.20-20 0.20-20
The first few characters in the line are equivalent to dpkg’s listing mode, as is
the second field (the package name). The third field indicates the currently
installed version of the package, and the fourth field indicates the most recent
available version of the package. (If an upgrade is available, for instance, the
new version of the package is displayed here.)
6. Highlight the package’s line, and the bottom line of the screen will display the
package’s short description. You can press Shift+D to turn the extended
description area back on and view the package’s long description.
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