adb shell ip route > addrs.txt
#Case 1:Nexus 7
#192.168.88.0/23 dev wlan0  proto kernel  scope link  src 192.168.89.48

#Case 2: Smartsian T1,Huawei C8813
#default via 192.168.88.1 dev eth0  metric 30
#8.8.8.8 via 192.168.88.1 dev eth0  metric 30
#114.114.114.114 via 192.168.88.1 dev eth0  metric 30
#192.168.88.0/23 dev eth0  proto kernel  scope link  src 192.168.89.152 metric 30
#192.168.88.1 dev eth0  scope link  metric 30

ip_addrs=$(awk {'if( NF >=9){print $9;}'} addrs.txt)

echo "the device ip address is $ip_addrs"