Best way to extract MAC address from ifconfig's output?

Question

What is the best way to extract the MAC address from ifconfig\'s output?

Sample output:

bash-3.00# ifconfig eth0        
eth0      Link          


        

Answer 1

You can do a cat under /sys/class/

cat /sys/class/net/*/address

Specifically for eth0

cat /sys/class/net/eth0/address

Answer 2

How about this one:

ifconfig eth0 | grep -Eo ..\(\:..\){5}

or more specifically

ifconfig eth0 | grep -Eo [:0-9A-F:]{2}\(\:[:0-9A-F:]{2}\){5}

and also a simple one

ifconfig eth0 | head -n1 | tr -s ' ' | cut -d' ' -f5`

Answer 3

I prefer the method described here (with slight modification): http://www.askdavetaylor.com/how_do_i_figure_out_my_ip_address_on_a_mac.html

ifconfig | grep "inet " | grep -v 127.0.0.1 | cut -d " " -f2

Which you can then alias to a short 'myip' command for future use:

echo "alias myip=\"ifconfig | grep 'inet ' | grep -v 127.0.0.1 | cut -d ' ' -f2\"" >> ~/.bash_profile

Answer 4

I would use:

ifconfig eth0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'

The -o will cause grep to only print the part of the line that matches the expression. [[:xdigit:]]{1,2} will match 1 or 2 hexidecimal digits (Solaris doesn't output leading zeros).

Answer 5

ifconfig en1 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}' 

• Replace "en1" with the name of the nic card "eth0" or remove altogether "en1" - easy and useful solution.

Answer 6

This works for me on Mac OS X:

ifconfig en0 | grep -Eo ..\(\:..\){5}

So does:

ifconfig en0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'

Both are variations of examples above.