preinst is in xfonts-terminus-dos 4.35-1.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 | #!/bin/sh
set -e
# Remove a no-longer used conffile
rm_conffile() {
    CONFFILE="$1"
    if [ -e "$CONFFILE" ]; then
        echo "Removing obsolete conffile $CONFFILE ..."
        rm -f "$CONFFILE"
    fi
}
case "$1" in
    install|upgrade)
	# Version 4.20-5.1 (etch) left obsolete conffile behind.
	rm_conffile "/etc/X11/fonts/X11R7/misc/xfonts-terminus-dos.alias"
	;;
    
    abort-upgrade)
	;;
    
    *)
        echo "preinst called with unknown argument \`$1'" >&2
        exit 1
	;;
esac
exit 0
 |