Change OS X network location automatically. This script will run when wireless network connection changes.

AutoChangeWirelessNetworkLocation.sh

#/bin/sh
#
# This script is woring on Mac OS X Mavericks 10.9.1.
#
# Usage:
#
# 1.Save this script in your binary directory.
#
# 2.Replace SSIDs and Labels in this script with your own environment.
#
# 3.Set "execute" permission to this script.
#    ex. $chmod 755 AutoChangeWirelessNetworkLocation.sh
#
# 4.Save the following XML document as your LaunchAgent ".plist" file.
#    ex. /Users/YOUR_ACCOUNT_NAME/Library/LaunchAgents/AutoChangeWireressNetworkLocation.plist
#
#<?xml version="1.0" encoding="UTF-8"?>
#<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
#<plist version="1.0">
#  <dict>
#    <key>Label</key>
#    <string>AutoChangeWirelessNetworkLocation</string>
#    <key>ProgramArguments</key>
#    <array>
#      <string>/path/to/the/AutoChangeWirelessNetworkLocation.sh</string>
#    </array>
#    <key>WatchPaths</key>
#    <array>
#      <string>/Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist</string>
#    </array>
#  </dict>
#</plist>
#
# 5.Replace the script path (/path/to/AutoChangeWirelessNetworkLocation.sh) in the ".plist" file with your own environment.
#
# 6.Execute the following command.
#    $launchctl load /path/to/the/AutoChangeWireressNetworkLocation.plist
#

exec 1>/dev/null 2>/dev/null

SSID=`/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -I | awk '/ SSID/ {print substr($0, index($0, $2))}'`


LOCATION1_SSID='COMPANY SSID'
LOCATION2_SSID='HOME SSID'

LOCATION1_LABEL='COMPANY LOCATION LABEL'
LOCATION2_LABEL='HOME LOCATION LABEL'
AUTOMATIC_LOCATION='Automatic'

case $SSID in
    $LOCATION1_SSID )
        COMMAND="scselect '$LOCATION1_LABEL'"
    ;;

    $LOCATION2_SSID )
        COMMAND="scselect '$LOCATION2_LABEL'"
    ;;

    * )
        COMMAND="scselect '$AUTOMATIC_LOCATION'"
    ;;
esac

eval $COMMAND

exit 0