preinst is in shorewall6-lite 4.5.21.6-1.
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 | #!/bin/sh -e
case "$1" in
upgrade)
# if we are upgrading from version < 3.4 then we have to rename the
# configuration file
if [ "$2" ] && dpkg --compare-versions "$2" lt "3.4"
then
if [ -f /etc/shorewall6-lite/shorewall.conf ]
then
ln /etc/shorewall6-lite/shorewall.conf /etc/shorewall6-lite/shorewall6-lite.conf
fi
fi
;;
*)
;;
esac
|