xscreensaver-command -time >/dev/null 2>&1 || xscreensaver &
# It can take a while for xscreensaver to start, wait until it's
- # ready.
+ # ready. a || b && c behaves like (a || b) && c.
while :; do
xscreensaver-command -lock || test $? -ne 255 && break
done