#!/bin/sh

total=`cat /proc/meminfo | grep "MemTotal" | awk '{print $2}'`
free=`cat /proc/meminfo | grep "MemFree" | awk '{print $2}'`
buffr=`cat /proc/meminfo | grep "Buffers" | awk '{print $2}'`
cache=`cat /proc/meminfo | grep "Cached" | awk '{print $2}'`

echo `echo $total $free $buffr $cache |\
    awk '{printf "%6.2fMB", ($1-($2+$3+$4))/1000}'`