UDP多播接收重复数据包

Question

GCC版本9.1.0

我希望这没关系

样本代码

#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <time.h>
#include <string.h>
#include <stdio.h>

#include <iostream>
#include <string>

using namespace std;

#define HELLO_PORT 12345
#define HELLO_GROUP "227.0.0.376"
#define INTRF           "10.0.21.1"
#define MSGBUFSIZE 256

int main(int argc, char *argv[])
{
    string source_iface(INTRF);
    string group(HELLO_GROUP);
    int port(HELLO_PORT);

    int fd;
    if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
    {
        perror("socket");
        exit(1);
    }

    u_int yes = 1;
    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0)
    {
        perror("Reusing ADDR failed");
        exit(1);
    }

    struct sockaddr_in addr;
    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    addr.sin_addr.s_addr = inet_addr(group.c_str());

   if (bind(fd,(struct sockaddr *)&addr, sizeof(addr)) < 0)
   {
        perror("bind");
        exit(1);
   }

   struct ip_mreq mreq;
   mreq.imr_multiaddr.s_addr = inet_addr(group.c_str());
   mreq.imr_interface.s_addr = inet_addr(source_iface.c_str());

    if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
    {
        perror("setsockopt");
        exit(1);
    }

    socklen_t addrlen;
    int nbytes;
    char msgbuf[MSGBUFSIZE];

    while (1)
    {
        memset(&msgbuf, 0, MSGBUFSIZE);

        addrlen = sizeof(addr);
        if ((nbytes = recvfrom(fd, msgbuf, MSGBUFSIZE, 0, (struct sockaddr *)&addr, &addrlen)) < 0)
        {
            perror("recvfrom");
            exit(1);
        }
        //msgbuf will be a structure, inside that there is a unique ID
    }

    return 0;
}

我也面临着类似的问题。 有人弄清楚了这个问题的原因吗？