#!/bin/sh


total="$(free -m | grep Mem: | awk '{ print $2 }')"
used="$(free -m | grep Mem: | awk '{ print $3 }')"
shared="$(free -m | grep Mem: | awk '{ print $5 }')"
free=$(expr $total - $used - $shared)
true_used=$(expr $shared + $used)

case $1 in
	total) echo $total;;
	used) echo $true_used;;
	free) echo $free;;
esac