Extracting MAC address from ifconfig output

Question

I am writing a #!bin/bash shell script to automate MAC spoofing. In the script that I have written I make the outputs of ifconfig -a | grep HWaddr equivalent to two different variables. The command ifconfig -a | grep HWaddr returns

eth0  Link encap:Ethernet HWaddr 00:00:00:00:00:00

and

wlan0 Link uncap: Ethernet HWaddr 00:00:00:00:00:00

but I want the command to return just the MAC address for wlan0.

The command `ifconfig` is not deprecated in MAC OS? Is the command deprecated in all Linux distributions or just a few? — Eric, Apr 20 '15 at 17:56
@Eric: For Linux, `ifconfig` is considered deprecated, but it doesn't do you a lot of harm to use it. It is highly unlikely to disappear any time soon. See http://serverfault.com/questions/458628/should-i-quit-using-ifconfig — Conspicuous Compiler, Apr 20 '15 at 17:57
@Eric: For OS X, you're right, `ifconfig` is still the preferred tool, but it is a significantly different beast than Linux's `ifconfig` and is, in fact, closer to Linux's `ip` in functionality. — Conspicuous Compiler, Apr 20 '15 at 17:58
I agree but I am shooting for cross-compatibility for all things *nix, whether it be Linux or Unix. — Eric, Apr 20 '15 at 18:01
@Cyrus `+1 Upvote` agreed, if question is tag for `linux` then why people talking about `OSX` and other flavor — Satish, Apr 20 '15 at 18:14
@Eric if you looking for all platform run-able script then you have to first detect `OS` and base on that run specific function or command to get `MAC` — Satish, Apr 20 '15 at 18:19

Satish · Accepted Answer · 2015-04-20T18:17:42.393

6

Try:

[root@linux ~]$ /sbin/ifconfig wlan0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'
00:25:90:F0:3F:92

By specifying wlan0 as the first argument to ifconfig, you are telling it you only want information about that particular interface, so you should only get a single line returned.

The grep command then searches for a MAC address in the output and prints only the portion of the ifconfig output which matches.

OR

Just for your script you can try follwong:

ifconfig -a | grep HWaddr | awk '{print $5}'

OSX

ifconfig en1 | awk '/ether/{print $2}'

edited Apr 20 '15 at 18:17

answered Apr 20 '15 at 17:49

Satish

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Do you mean `wlan0` instead of `eth0` ? – Eric Apr 20 '15 at 17:53
I have edited answer, you can just use `awk` to extract MAC field – Satish Apr 20 '15 at 17:56
Do you think that `ifconfig -a | grep HWaddr | awk '{print $5}'` is preferable over `cat /sys/class/net/wlan0/address`? If so, why? – Eric Apr 20 '15 at 18:08
@Eric there are many way to extract `MAC` address its depend on you, which one satisfying your need. – Satish Apr 20 '15 at 18:12
1

Brrrr.... `grep` and `awk` in the same pipe-snake??? It can be reduced to: `awk '/HWaddr/{print $5}'` – TrueY Apr 20 '15 at 18:18
What's wrong with `grep` and `awk` in the same pipe-snake? – Eric Apr 20 '15 at 18:30
Don't forget to answer question if it's helpful – Satish May 02 '15 at 23:33
1

It was helpful. Thanks, Satish. – Eric Jun 19 '15 at 21:48

Extracting MAC address from ifconfig output

1 Answers1

OR

OSX