Sending a broadcast message using raw sockets
Rob Williscroft
rtw at rtw.me.uk
Mon Jan 21 04:10:06 EST 2013
Peter Steele wrote in
news:f37ccb35-8439-42cd-a063-962249b44903 at googlegroups.com in
comp.lang.python:
> I want to write a program in Python that sends a broadcast message
> using raw sockets. The system where this program will run has no IP or
> default route defined, hence the reason I need to use a broadcast
> message.
>
> I've done some searches and found some bits and pieces about using raw
> sockets in Python, but I haven't been able to find an example that
> explains how to construct a broadcast message using raw sockets.
>
> Any pointers would be appreciated.
This is part of my Wake-On-Lan script:
def WOL_by_mac( mac, ip = '<broadcast>', port = 9 ):
import struct, socket
a = mac.replace( ':', '-' ).split( '-' )
addr = struct.pack( 'B'*6, *[ int(_, 16) for _ in a ] )
msg = b'\xff' * 6 + addr * 16
s = socket.socket( socket.AF_INET, socket.SOCK_DGRAM )
s.setsockopt( socket.SOL_SOCKET, socket.SO_BROADCAST, 1 )
s.sendto( msg, ( ip, port ) )
s.close()
The mac address is 6 pairs of hex digits seperated by '-' or ':'.
http://en.wikipedia.org/wiki/Wake-on-LAN
Rob.
More information about the Python-list
mailing list