#!/bin/sh
MEMORY_USED=$(free -h | awk 'NR==2 {print $3}')

# freebsd (and maybe better for linux too)
#PAGES_WIRED=$(sysctl vm.stats.vm.v_wire_count | awk '{print $2}')
#PAGES_ACTIVE=$(sysctl vm.stats.vm.v_active_count | awk '{print $2}')
#PAGES_DIRTY=$(sysctl vm.stats.vm.v_laundry_count | awk '{print $2}')
#TOTAL_PAGES=$(echo "scale=0; $PAGES_WIRED+$PAGES_ACTIVE+$PAGES_DIRTY" | bc)
#
#BYTES_USED=$(echo "scale=0; $TOTAL_PAGES*4096" | bc)
#
#if [ $BYTES_USED -ge 1073741824 ]; then
#  MEMORY_USED="$(echo "scale=1; $BYTES_USED/1024^3" | bc) GiB"
#else
#  MEMORY_USED="$(echo "scale=1; $BYTES_USED/1024^2" | bc) MiB"
#fi

echo $MEMORY_USED