On Wed, 2007-08-22 at 20:46 +0200, Johannes Berg wrote:

The two different wireless code bases both define macros to ease
printing MAC addresses:

There are also several different uses of the equivalent of

	printk("%02x",addr[0])
	for (i=1; i<6; i++)
		printk(":%02x",addr[i]);

to print an ethernet MAC address.

http://www.uwsg.iu.edu/hypermail/linux/net/0602.1/0002.html

As not all device MAC addresses are 6 bytes, colon separated,
perhaps an appropriate ethernet/tr MAC designation is EUI48.

http://standards.ieee.org/regauth/oui/tutorials/EUI48.html