prerm is in libqt4-dev 4:4.8.1-0ubuntu4.
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 | #!/bin/sh
set -e
case "$1" in
upgrade) ;;
remove|failed-upgrade|deconfigure)
update-alternatives --remove moc "/usr/bin/moc-qt4"
update-alternatives --remove uic "/usr/bin/uic-qt4"
;;
esac
|