prerm is in boinc-app-seti-graphics 8.00~svn3701-1.
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 33 34 35 36 37 38 39 40 41 42 43 44 | #!/bin/sh
# prerm script for boinc-app-seti-graphics
set -e
BOINC_DIR=/var/lib/boinc-client
PROJECT=seti-graphics
init_boinc_client()
{
    if which invoke-rc.d >/dev/null 2>&1; then
        invoke-rc.d boinc-client $1
    else
        /etc/init.d/boinc-client $1
    fi
}
case "$1" in
    remove)
        # Stop the core client and wait one second to give it the
        # chance to shut down gracefully before removing the S@h
        # application. Start the client then again.
        init_boinc_client stop
        sleep 1
        update-boinc-applinks --remove --project=$PROJECT --data-dir=$BOINC_DIR
        init_boinc_client start
    ;;
    
    upgrade)
        update-boinc-applinks --remove --project=$PROJECT --data-dir=$BOINC_DIR
    ;;
    failed-upgrade|deconfigure)
    ;;
    *)
        echo "prerm called with unknown argument \`$1'" >&2
        exit 1
    ;;
esac
exit 0
 |