#!/bin/bash

if [ "$( /usr/bin/id --user )" -ne 0 ] ; then
  printf "U have to be root\\!"
  exit 1
fi

if [ ! -x "/sbin/ethtool" ] ; then
  printf "U have to install ethtool first\\!"
  exit 2
fi

ETH="eth0"
CNT=0

while true ; do
  if ! /sbin/ethtool "${ETH}" 2>/dev/null | /bin/grep "Link detected: yes" 1>/dev/null ; then
    (( CNT++ ))
  else
    CNT=0
  fi
  if [ "${CNT}" -gt 6 ] ; then /home/pi/bin/sesame close ; fi
  sleep 6
done

exit 0