prerm is in scim-bridge-agent 0.4.16-2ubuntu5.
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  | #!/bin/sh
set -e
ua_remove () {
	update-alternatives \
        --remove xinput-$1 \
        /etc/X11/xinit/xinput.d/$2 ;
}
case "$1" in
    remove|upgrade|deconfigure)
        ua_remove all_ALL scim-bridge
        ua_remove ja_JP   scim-bridge
        ua_remove ko_KR   scim-bridge
        ua_remove zh_CN   scim-bridge
        ua_remove zh_TW   scim-bridge
        ua_remove zh_HK   scim-bridge
        ua_remove zh_SG   scim-bridge
	;;
    failed-upgrade)
	;;
    *)
	echo "prerm called with unknown argument \`$1'" >&2
	exit 1
   ;;
esac
exit 0
 |