[VxWorks] vxworks UDP 组播发送

xjc9837 2010-4-8 15:56 楼主

各位大哥帮忙看看我的组播发送函数，sendto返回老是ERROR，发送失败，是什么原因？谢谢。
struct sockaddr_in    local;
struct sockaddr_in    target;
struct ip_mreq          ipMreq;

int                      localfd;
int    i,recvbytes,sendbytes;
char    message[REQUEST_MSG_SIZE];

struct ip_mreq mcast;
client_tx=0;
   client_tx_err=0;

bzero((char *)&local,sizeof(local));
local.sin_family = AF_INET;
local.sin_addr.s_addr = inet_addr("202.195.114.224");
local.sin_port = htons(SERVER_PORT_NUM);

if((localfd = socket( AF_INET, SOCK_DGRAM, 0)) == ERROR)
{
   printf("frame send Task socket() error:%s\n",strerror(errno));
   return ERROR;
}
if(bind(localfd, (struct sockaddr *)&local, sizeof(struct sockaddr_in))==ERROR)
{
   printf("frame send Task bind() error:%s\n",strerror(errno));
   return ERROR;
}
ipMreq.imr_multiaddr.s_addr = inet_addr("224.1.0.1");
ipMreq.imr_interface.s_addr = inet_addr("202.195.114.224");
if(setsockopt(localfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *)&ipMreq, sizeof(ipMreq)) == ERROR)
{
   printf("setsockopt error, %s.\n", strerror(errno));
}
else
{
   printf("join  group ok.\n");
}

bzero((char *)&target,sizeof(target));
target.sin_family =  AF_INET;
target.sin_addr.s_addr = inet_addr("224.1.0.1");
target.sin_port = htons(5002);



memset(message, 'Z', REQUEST_MSG_SIZE);
FOREVER
      {
            /*memset(message, client_tx & 0xff, REQUEST_MSG_SIZE);*/
            memset(message, 'Z', REQUEST_MSG_SIZE);
            delays(1250000 / 3);
            /*taskDelay(1);*/

            if((sendbytes=sendto (localfd, (char *) message, length, 0,(struct sockaddr *) &target,
                              sizeof(struct sockaddr_in)) == ERROR))
            {
               printf("mcastSend sendto errno:0x%x\n", strerror(errno));
               break;
            }



            if (sendbytes != length)
            {
               client_tx_err++;
               break;
            }
            else
               client_tx++;

            if(client_tx==count)
            {

               printf("count value is %d\n", count);
               break;
            }

   }

  close (localfd);
  return OK;