Python string extraction from Subprocess

Question

Hi I am currently coding a random program at the moment, that effectively needs to see my MAC address.

This is what I have at the moment:

import subprocess

def get_mac():

    mac_addr = subprocess.check_output(["ifconfig", "wlan0"])

Output from where i want the HWaddr extracted:

ifconfig wlan0
wlan0     Link encap:Ethernet  HWaddr 00:1b:11:1e:97:29  
          inet addr:10.1.1.6  Bcast:10.1.1.255  Mask:255.255.255.0                                                                                                                  
          inet6 addr: fe80::21b:11ff:fe1e:9729/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:91394 errors:0 dropped:0 overruns:0 frame:0
          TX packets:58894 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:115550581 (115.5 MB)  TX bytes:6097577 (6.0 MB)

So now I have the whereabouts of the MAC, but how would I extract it in that exact format? I looked around and couldn't fine anything other than URL extractions and such.

All I could find were re.search hich doesnt help me at all as I need to find a different MAC possible every time. Thanks

EDIT:

Sorry it's 5:30 and I am a bit tired. I realised I didnt even finish my question sorry. Not even the code :/ Edited now

Answer 1

If you're on linux, you may try this to get the MAC address:

iface = 'wlan0'
mac_addr = open('/sys/class/net/%s/address' % iface).read().rstrip()

For general string extraction, you may use the re module:

import subprocess, re

RE_MAC = re.compile(r'\bHWaddr\s+(((?(2):|)[\dA-Fa-f]{2}){6})\b')
match = RE_MAC.search(subprocess.check_output(["ifconfig", "wlan0"]))
if match:
    mac_addr = match.group(1)

Note that my version of ifconfig (net-tools 1.60) uses ether rather than HWaddr, illustrating one problem of parsing the output of such programs.