Example shell script to confirm, with optional override, before doing something destructive.

confirm_delete.sh

#!/bin/sh
#
# confirm_delete.sh - Example shell script to confirm, with optional override, before doing something destructive.
#
removeit() {
    # Code that does something destructive.
    exit 0
}
if [ "$1" = "--force" ]; then
    removeit
fi

while : ; do
    read -p "Are you sure want to do this? [y/N] " this
    case "${this}" in
        Y|n ) removeit;;
        N|n|'' ) exit 0;;
        * ) echo "Y or N";;
    esac
done