a=0; while [ $a -lt 255 ]
do
  b=0; while [ $b -lt 255 ]
  do
    echo sweeping through 10.$a.$b.*
    c=0; while [ $c -lt 255 ]
    do
      c=`echo $c+1 | bc`
      if ping -t 1 -i 1 -c 1 10.$a.$b.$c | grep -q '0 packets received'
      then
   	  echo -n " "
      else
     	  echo -n "."
      fi
    done
    echo
    b=`echo $b+1 | bc`
  done
  a=`echo $a+1 | bc`
done