debconf

debconf-set-selections [file]
debconf-get-selections []

debconf-set-selections [file]
    Imports pre-selections (answers to debconf questions) from a file. This is useful for automating package installations.

debconf-get-selections []
    Exports the current selections (answers to debconf questions) for a specified package, or all packages if none is specified, to standard output.

The debconf system is a configuration management system for Debian packages. Its primary goal is to provide a consistent and user-friendly way for packages to ask configuration questions during installation and upgrades.

It separates configuration from package scripts, allowing for more flexible and automated installations. Debconf uses a database to store the answers to configuration questions, ensuring that packages don't need to re-ask the same questions repeatedly. It supports different user interfaces, including a text-based interface, a curses-based interface, and a graphical interface, allowing users to choose the interface that best suits their needs.

Packages interact with debconf using the debconf protocol via a command-line tool, allowing them to ask questions, set default values, and retrieve user responses. The system is designed to be robust and handles various scenarios, such as interrupted installations and package upgrades. The debconf database allows administrators to preseed answers to configuration questions, enabling unattended installations.

Changes made through debconf may be overwritten during package upgrades if the maintainer scripts update the debconf database.

Debconf supports several user interfaces for displaying configuration questions, including:
* dialog: A text-based interface using the 'dialog' program.
* readline: A simple text-based interface.
* curses: A curses-based interface providing a more interactive experience.
* gtk: A graphical interface using the GTK+ toolkit.

Preseeding is the process of providing answers to debconf questions before a package is installed. This is typically done using the debconf-set-selections command or by placing preseed files in the /var/cache/debconf/preseed/ directory. Preseeding allows for automated installations and reduces the need for user interaction during package installations.

Debconf was developed to improve the configuration process of Debian packages and replace the older, less flexible methods. It aimed to separate configuration from package scripts and provide a more consistent user experience. Over time, it has become a standard part of the Debian ecosystem and has been adopted by other distributions as well. Its development has focused on improving its robustness, user interface, and ability to handle complex configuration scenarios.

dpkg(1), apt(8), apt-get(8)