help=" + - or (pg)up,dn to adjust tempo
any key to enter a numeric tempo
h for help
q to quit"
printf '\e[?25l\e[11;1]\e[H\e[2J%i bpm' $bpm
[ $TERM = linux ] || printf '\n\n%s' \
'consider switching to plain linux console'
# the escape for changing bell length only works there, leading to
# inaccuracy when some terms have a long bleat -- not to mention
# some don't even have a bell at all
amixer -q set Beep unmute # or the equivalent command for non-alsa setups, if needed
# if still mute, try (as root) modprobe pcspkr
trap 'amixer -q set Beep mute; exit' INT
while [ "$input" ] || printf '\a'; do
unset input
read -sn1 -t $interval input || continue
case "$input" in
+|A|5)
(( bpm++ ))
;;
-|B|6)
(( bpm-- ))
;;
$'\E'|[|\~)
# up/down keys need this, despite WORKING FINE JUST A SECOND AGO
;;
q)
amixer -q set Beep mute
printf '\e[?25h\e[H\e[JGood job %s for practicing.\n' "$USER"
exit
;;
h)
printf '\e[H\e[J%s\n\n\t%s' "$help" "press any key"
read -n 1
;;
*)
printf '\e[H\e[JEnter a tempo: '
old=$bpm
read bpm
;;
esac
if (( i=6000/bpm-1, sec = i/100, ms = i%100, bpm )); then
printf -v interval "%i.%02i" $sec $ms
# HA, goodbye numfmt, my last external process
else bpm=$old; fi
