1 #!/usr/bin/python
2 #coding=utf-8
3 #发送端
4 import sys,struct,socket
5 from time import sleep
6
7 message="hello"
8 message1="nihao"
9
10 multicast_group=('224.3.29.73',10003)
11 multicast_group1=('224.3.29.74',10004)
12
13 sock=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
14
15 sock.timeout(3)
16
17 ttl=struct.pack('b',1) #将数字1转换成无符号字符类型.在python中没有这种类型,但是内核需要,所以转换
18
19 sock.setsockopt(socket.IPPROTO_IP,socket.IP_MULTICAST_TTL,ttl)
20
21 try:
22 while 1:
23 sleep(2)
24 sent=sock.sendto(message,multicast_group)
25 sent=sock.sendto(message1,multicast_group1)
26
27 print >>sys.stderr,"waiting to receive"
28
29 try:
30 data,server=sock.recvfrom(1024)
31 except sock.timeout:
32 print >>sys.stderr,"time out ,no more response"
33 break
34 else:
35 print >>sys.stderr,"received %s from %s"%(data,server)
36 finally:
37 print >>sys.stderr,"closing socket"
38 sock.close()
1 #!/usr/bin/python
2 #接收端
3 import socket
4 import sys
5 import struct
6
7 multicast_group = '224.3.29.72'
8 server_address = ('',10001)
9
10 sock = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
11
12 sock.bind(server_address)
13
14 group = socket.inet_aton(multicast_group)
15 mreq = struct.pack('4sL',group,socket.INADDR_ANY)
16 sock.setsockopt(socket.IPPROTO_IP,socket.IP_ADD_MEMBERSHIP,mreq)
17
18 while True:
19 print >>sys.stderr,'\nwaiting to receive message'
20 data,address = sock.recvfrom(1024)
21
22 print >>sys.stderr,'received %s bytes from %s'%(len(data),data)
23 print >>sys.stderr,'sending acknowledgement to',address
24 sock.sendto('gaozhiqiangf',address)
25
