Datasheet

Part I ✦ The Fundamentals

but you can also invoke them later on to reconfigure the package. This is done by

running

dpkg-reconfigure packagename:

hostname:~# dpkg-reconfigure debconf

Reconfiguring debconf allows you to set a variety of parameters used to display

and process questions asked via packaged

debconf scripts. The first question

debconf’s own configuration script asks is “What interface should be used for

configuring packages?” You can safely leave it at the default. After you’ve selected

which interface you’d like to use, press Enter. You’re then asked what priority of

questions you’d like to see. Low-priority questions aren’t displayed by default;

they’re usually only of interest to obsessive-compulsive knob-twiddlers like myself.

I selected medium-priority questions, and you should as well. Unlike changing the

debconf interface, changing which questions are asked will result in subtly differ-

ent configuration files, which may break the instructions given in this book. When

you’re done with this book, or when you’re familiar with the system as a whole,

feel free to reconfigure debconf and choose whichever priority level you’d like.

Configuration file handling

Configuration files are always handled specially in Debian because they’re far more

important than most other software files. Configuration files are meant to be edited

by the administrator, and as such may have hours of work put into them. Given

that, and because your installation can break badly if a package blindly overwrites

your carefully crafted configuration file, extra prompts are displayed whenever

something damaging might happen.

Prompts are displayed whenever:

1. A new package is being installed for the first time, and there is a preexisting

configuration file — perhaps copied from an older installation.

2. A package is being upgraded, but the administrator has manually changed a

configuration file so that it’s no longer the same one that was contained in the

package.

Prompts are not displayed when:

1. The administrator has removed a configuration file; if you want to get a config-

uration file back from a package, you need to purge and reinstall it.

2. A new version of a configuration file exists in the new version of the package,

and the administrator hasn’t changed the current version.

Note

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