#!/bin/sh
while true
do 
	volume="$(mpc volume | awk '{print $2}' | cut -f1 -d'%')"
	choice="$(echo "plus\nmin" |
		dmenu -g 2 -l 1 -p "$volume" |
		sed 's/plus/+/;s/min/-/')"
	test -z "$choice" && break
	nb="$(dmenu -g 2 -l 1 -p "$volume$choice" < /dev/null)"
	test -z "$nb" && break
	mpc volume "$choice$nb"
done