http://l3tczdiiwoo63iwxty4lhs6p7eaxop5micbn7vbliydgv63x5zrrrfyd.onion/man-page/privoxy-man-page.html
--user user[.group] After (optionally) writing the PID file, assume the user ID of user and the GID of group , or, if the optional group was not
given, the default group of user . Exit if the privileges are not
sufficient to do so.