Section: Debconf (1)
echo commands | debconf-communicate [options] [package]
debconf-communicate allows you to communicate with debconf on the fly, from the command line. The package argument is the name of the package which you are pretending to be as you communicate with debconf, and it may be omitted if you are lazy. It reads commands in the form used by the debconf protocol from stdin. For documentation on the available commands and their usage, see the debconf specification.
The commands are executed in sequence. The textual return code of each is printed out to standard output.
echo get debconf/frontend | debconf-communicate
Joey Hess <firstname.lastname@example.org>