3G work with office network

phillips@phillips-ThinkPad-T420:~$ cat bin/3Gwifi_net_office.sh 
#!/bin/sh
# For dropbox sync ~/Dropbox 
# This script help update routing table for forward main traffic to wifi -> 3G 
# and keep office network connection via eth0
wlanip=`ip -4 addr show wlan0  | grep inet| awk  '{print $2}' | awk -F \/  '{print $1}'`
newgw=`echo $wlanip | awk '{split($0,array,".")} END{print array[1]”.”array[2]”.”array[3]"."1}'`
case $1 in 
    start)
        route add default gw $newgw
        route add -net 172.22.20.0 netmask 255.255.254.0 gw 172.22.2.1
        route add -net 172.22.12.0 netmask 255.255.254.0 gw 172.22.2.1
        route add -net 172.22.4.0 netmask 255.255.254.0 gw 172.22.2.1
        route add -net 172.22.16.0 netmask 255.255.254.0 gw 172.22.2.1
        ;;
    stop)
        route del default gw $newgw
        route del -net 172.22.20.0 netmask 255.255.254.0 
        route del -net 172.22.12.0 netmask 255.255.254.0
        route del -net 172.22.4.0 netmask 255.255.254.0
        route del -net 172.22.16.0 netmask 255.255.254.0
        route add default gw 172.22.2.1
        ;;
esac