#!/usr/bin/env python

import ctypes
import socket
import struct

def get_macaddress(host):
    """ Returns the MAC address of a network host, requires >= WIN2K. """
    
    # Check for api availability
    try:
        SendARP = ctypes.windll.Iphlpapi.SendARP
    except:
        raise NotImplementedError('Usage only on Windows 2000 and above')
        
    # Doesn't work with loopbacks, but let's try and help.
    if host == '127.0.0.1' or host.lower() == 'localhost':
        host = socket.gethostname()
    
    # gethostbyname blocks, so use it wisely.
    try:
        inetaddr = ctypes.windll.wsock32.inet_addr(host)
        if inetaddr in (0, -1):
            raise Exception
    except:
        hostip = socket.gethostbyname(host)
        inetaddr = ctypes.windll.wsock32.inet_addr(hostip)
    
    buffer = ctypes.c_buffer(6)
    addlen = ctypes.c_ulong(ctypes.sizeof(buffer))
    if SendARP(inetaddr, 0, ctypes.byref(buffer), ctypes.byref(addlen)) != 0:
        raise WindowsError('Retreival of mac address(%s) - failed' % host)
    
    # Convert binary data into a string.
    macaddr = ''
    for intval in struct.unpack('BBBBBB', buffer):
        if intval > 15:
            replacestr = '0x'
        else:
            replacestr = 'x'
        macaddr = ''.join([macaddr, hex(intval).replace(replacestr, '')])
    
    return macaddr.upper()

if __name__ == '__main__':
    print 'Your mac address is %s' % get_macaddress('localhost')
