save-bash-history

#!/bin/bash
HISTFILE=~/.bash_history
x#set -o history #turns on for this non-interactive script
history -a # appends current, working?
#su user "history -a"
#exec sudo -u user -- "$0" "$@"
# every day at midnight cron.daily append current history to a backup
comm -23 .bash_history .bash_history-bak >> .bash_history-bak # Show lines that only exist in file a: