/sbin/ifconfig eth0 | grep 'inet addr:' | cut -d: -f2 | awk '{print $1}'
# 135.79.246.80
$ip = exec('/sbin/ifconfig eth0 | grep "inet addr:" | cut -d: -f2 | awk "{print \$1}"');
echo $ip;
# 135.79.246.80
import subprocess
ip = subprocess.Popen('/sbin/ifconfig eth0 | grep "inet addr:" | cut -d: -f2 | awk "{print \$1}"', shell=True, stdout=subprocess.PIPE).stdout.read().strip()
print( ip )
import socket, fcntl, struct
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
ip = socket.inet_ntoa(fcntl.ioctl(s.fileno(),0x8915,struct.pack('256s','eth0'))[20:24])
print( ip )