post_install(){
    echo "Program diffimg (and man page) has been renamed as DiffImg because it conflicts with graphviz"
    #which xdg-icon-resource >/dev/null 2>&1 && xdg-icon-resource forceupdate || true
    echo "update desktop mime database..."
    update-desktop-database -q
}
post_upgrade(){
    post_install
}
post_remove(){
    #which xdg-icon-resource >/dev/null 2>&1 && xdg-icon-resource forceupdate || true
    echo "update desktop mime database..."
    update-desktop-database -q
}