Deleting unused config files in Debian
Getting a list of unused packages (not the installed ones): dpkg –list | grep -v -E “^ii”
Purging packages list: dpkg –purge packagename
So doing all this in one line would be something like:
dpkg –purge dpkg --list | grep -v -E "^ii" | perl -ne '/^rc\s+([^\s]+)/ && print “$1 “;’
Be careful!