Question

I would like to get the first interface that is up on a linux machine. I am using subproces and I have the following piece of code :

def get_eth_iface():
    awk_sort = subprocess.Popen( ["-c", "ifconfig | cut -d ' ' -f 1 | grep eth | head -n 1" ], stdin= subprocess.PIPE, shell=True )
    awk_sort.wait()
    output = awk_sort.communicate()[0]

But with this result will be printed to the console and won’t be saved to the variable. How can I redirect this to the variable ?

Answer 1

Redirect the stdout to subprocess.PIPE. Following works for me.

import subprocess
def get_eth_iface():
    awk_sort = subprocess.Popen( ["dir" ], stdin= subprocess.PIPE, stdout= subprocess.PIPE)
    awk_sort.wait()
    output = awk_sort.communicate()[0]
    print output.rstrip()
get_eth_iface()