#!/usr/bin/env python
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#~ Imports
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
import sys
import time
import socket
import select
import struct
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#~ LibC definitions of if_nametoindex
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
if_nametoindex = None
if if_nametoindex is None:
try: import ctypes
except ImportError: pass
else:
_libc = ctypes.cdll.libc
def if_nametoindex(interfaceName):
# if you have a better way to get the interface index, I'd love to hear
# it... You are supposed to be able to leave the interface number as 0,
# but I get an exception when I try this. (MacOS 10.4) It may be because
# it is a multihomed device...
return _libc.if_nametoindex(interfaceName)
if if_nametoindex is None:
try: import dl
except ImportError: pass
else:
_libc = dl.open('libc.so')
def if_nametoindex(interfaceName):
# if you have a better way to get the interface index, I'd love to hear
# it... You are supposed to be able to leave the interface number as 0,
# but I get an exception when I try this. (MacOS 10.4) It may be because
# it is a multihomed device...
return _libc.call('if_nametoindex', interfaceName)
if if_nametoindex is None:
raise RuntimeError("No implementation allowing access to if_nametoindex available")
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#~ Definitions
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
maddr = ('ff12::4242', 4242)
def ipv6Multicast(host='::1', maddr=maddr):
haddr = socket.getaddrinfo(host, maddr[1], socket.AF_INET6, socket.SOCK_DGRAM)[0][-1]
maddr = socket.getaddrinfo(maddr[0], maddr[1], socket.AF_INET6, socket.SOCK_DGRAM)[0][-1]
sock = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
if hasattr(socket, "SO_REUSEPORT"):
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_LOOP, 1)
sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_HOPS, 5)
ifn = haddr[3] or if_nametoindex('lo0')
ifn = struct.pack("I", ifn)
sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_IF, ifn)
group = socket.inet_pton(socket.AF_INET6, maddr[0]) + ifn
sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_JOIN_GROUP, group)
sock.bind(haddr)
sock.setblocking(False)
return sock, maddr
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#~ Main
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
if __name__=='__main__':
# change host to use your IPv6 address...
sock, maddr = ipv6Multicast(host='::1')
# send initial message
msg = ' '.join(sys.argv[1:])
msg = msg or 'IPv6 multicast recipie'
sock.sendto(msg, maddr)
try:
t0 = 0
while 1:
tn = time.time()
if tn-t0 > 1:
sock.sendto('blink: '+msg, maddr)
t0 = tn
if select.select([sock],[],[],1)[0]:
# we have a message... print what was sent!
print sock.recvfrom(1024)
except KeyboardInterrupt:
pass
