Enable/disable wireless on Mountain Lion when eth is connected

gistfile1.txt

#!/bin/bash

#
# This script will turn ON AirPort only if it was turned OFF before
# by this script.
# If AirPort was turned off manually, it will not be automatically enabled
#

AIRPORT=""
ALLINTERFACES=""

beacon=/var/log/AirPortBeacon.beacon

IFS='
'

SW_VER=`/usr/bin/sw_vers -productVersion`

APNAME="Wi-Fi"

#
# Look for AirPort interface and Create list of watched network interfaces
# We are looking for all Ethernet interfaces and Bluetooth PAN
#

for intf in `/usr/sbin/networksetup -listnetworkserviceorder | grep "^(H"`
do
   IFS=':,)'
   set $intf
   if [[ ($2 =~ Ethernet ) || ( $2 =~ "Bluetooth PAN" ) ]];
   then
      ALLINTERFACES="${ALLINTERFACES} $4";
   fi
   if [[ ($2 =~ ${APNAME} ) ]]; then AIRPORT=$4; fi
done

IFS=' 	
'

#
# If no interfaces to watch or no AirPort found - do nothing
#

if ( ([ -z "${ALLINTERFACES}" ]) || ([ -z ${AIRPORT} ]) );
then
  echo "Nothing to do"
  exit 0;
fi

#
# What software version we are running ?
# networksetup syntax changed in Snow Leopard
#

AP_CMD="/usr/sbin/networksetup -setairportpower ${AIRPORT}"
AP_STATUS="/usr/sbin/networksetup -getairportpower ${AIRPORT}"

ap_state=`${AP_STATUS} | awk '{ print $NF }'`
echo $ap_state
#
# Check if watched interface have IP address assigned
# or (as an alternative - check if the interface is connected or not)
#

for ethintf in ${ALLINTERFACES}
do

   # Check if IPv4 address is assigned
   # 
    ifconfig ${ethintf} 2>/dev/null | grep "inet " > /dev/null

   #
   # Check if interface is active
   #
   # ifconfig ${ethintf} 2>/dev/null | grep "status: active" > /dev/null

   assigned=$?
   
   if [ $assigned -eq 0 ];
   then
      if [ "${ap_state##* }" == "On" ];
      then
	if [ ! -f ${beacon} ];
	then
	  echo "Turning wi-fi off" 
          ${AP_CMD} off
	fi
         touch ${beacon}
      fi
      exit 0
   fi
done

if [ -f ${beacon} ];
then
  if [ "${ap_state##* }" == "Off" ];
  then
    echo "Turning wi-fi on"
    ${AP_CMD} on
  fi
    rm ${beacon}
fi
exit 0

Ciao, dove va piazzato e come si usa?