一些组播代码

玩组播，收集部分代码，调测通过。

mrecv.c

#include 
#include 
#include <string.h>

#include 
#include 
#include 
#include 
#include in.h>
#include if.h>

#define MCAST_GRP "224.1.1.1"
#define MCAST_PORT 5566
#define MAXBUF 10240

int main()
{
    int n, r, sockfd = -1;
    struct sockaddr_in srv, cli;
    struct ip_mreq mreq;
    char buf[MAXBUF];

    memset( &srv, 0, sizeof(struct sockaddr_in) );
    memset( &cli, 0, sizeof(struct sockaddr_in) );
    memset( &mreq, 0, sizeof(struct ip_mreq) );

    srv.sin_family = AF_INET;
    srv.sin_port = htons(MCAST_PORT);
    if (inet_aton(MCAST_GRP, &srv.sin_addr) < 0) {
        fprintf(stderr, "inet_aton");
        return -1;
    }
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
        fprintf(stderr, "socket");
        return -1;
    }
    if (bind(sockfd, (struct sockaddr *)&srv, sizeof(srv)) < 0) {
        fprintf(stderr, "bind");
        return -1;
    }
    if (inet_aton(MCAST_GRP, &mreq.imr_multiaddr) < 0) {
        fprintf(stderr, "inet_aton");
        return -1;
    }

    {
        struct ifreq ifreq;

        strncpy(ifreq.ifr_name, "eth0", IFNAMSIZ);
        if (ioctl(sockfd, SIOCGIFADDR, &ifreq) < 0) {
            fprintf(stderr, "ioctl");
            return -1;
        }

        memcpy(&mreq.imr_interface,
               &((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr,
               sizeof(struct in_addr));
    }

    if (setsockopt(sockfd, SOL_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) {
        fprintf(stderr, "setsockopt");
        return -1;
    }

    while(1) {
        if ((n = recv(sockfd, buf, MAXBUF, MSG_DONTWAIT)) > 0) {
            buf[n] = 0;
            //fprintf(stdout, "message: %s", buf);
            printf("received %s\n", buf);
        }
        else if (0 == n)
            break;
    }
    return 0;
}

mrecv.py

#!/usr/bin/env python
import socket
import struct

MCAST_GRP = '224.1.1.1'
MCAST_PORT = 5566

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind((MCAST_GRP, MCAST_PORT))
mreq = struct.pack("4sl", socket.inet_aton(MCAST_GRP), socket.INADDR_ANY)

sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

while True:
    print 'recv', sock.recv(10240)

msend.c

#include 
#include 
#include <string.h>

#include 
#include 
#include 
#include 
#include in.h>
#include if.h>

#define MCAST_GRP "224.1.1.1"
#define MCAST_PORT 5566
#define MAXBUF 10240

int main()
{
    int n, r, sockfd = -1;
    struct sockaddr_in srv, cli;
    struct ip_mreq mreq;
    char buf[MAXBUF];

    memset( &srv, 0, sizeof(struct sockaddr_in) );
    memset( &cli, 0, sizeof(struct sockaddr_in) );
    memset( &mreq, 0, sizeof(struct ip_mreq) );

    srv.sin_family = AF_INET;
    srv.sin_port = htons(MCAST_PORT);
    if (inet_aton(MCAST_GRP, &srv.sin_addr) < 0) {
        fprintf(stderr, "inet_aton");
        return -1;
    }
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
        fprintf(stderr, "socket");
        return -1;
    }

    while(1) {
        sendto(sockfd, "Hello World", strlen("Hello World"), 0,
                        (struct sockaddr*)&srv,sizeof(struct sockaddr_in));
        sleep(1);
    }
}

msend.py

#!/usr/bin/env python
import socket

MCAST_GRP = '224.1.1.1'
MCAST_PORT = 5566

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, 2)
while True:
    import time, random
    _content = str(random.random())
    print "send", _content
    sock.sendto(_content, (MCAST_GRP, MCAST_PORT))
    time.sleep(3)

 

转载于:https://www.cnblogs.com/luckybug/archive/2012/07/05/2577575.html