[lwip-users] Multicast: Not receiving multicast messages

[saad saeed]

Dear All,

I am trying to receive multicast traffic, I have used the following code.

------------------------------------------------------------------------------------------

int s;

struct sockaddr_in addr;

struct sockaddr_in from;

char buff[80];

s=lwip_socket(AF_INET,SOCK_DGRAM,0u);

if(s==-1)

{

 PRINTF("Socket not created.\r\n");

}

else

{

 PRINTF("Socket created.\r \n");

 addr.sin_family=AF_INET;

 addr.sin_port=htons(7);

 addr.sin_addr.s_addr=inet_addr("192.168.1.105");

 if(lwip_bind(s,(struct sockaddr*)&addr,sizeof(addr)) < 0)

 {

  PRINTF("Binding error. \r\n");

 }

 else

 {

  PRINTF("Binding recieve.\r \n");

     // use setsockopt() to request that the kernel join a multicast group

     struct ip_mreq mreq;

     memset(&mreq, 0, sizeof(mreq));

  mreq.imr_multiaddr.s_addr = inet_addr("239.255.255.250");

     mreq.imr_interface.s_addr = inet_addr("192.168.1.105");

     if (lwip_setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char*) &mreq, sizeof(mreq)) < 0)

  {

      PRINTF("Membership unsuccessfull \r\n");

     }

  else

  {

     PRINTF("Membership successfull \r\n");

  }

  socklen_t size  =sizeof(from);

  if(lwip_recvfrom(s,&buff,80,0,(struct sockaddr*)&from,&size) < 0)

  {

   PRINTF("Failed to recieve a message. \r\n");

  }

  else

  {

   PRINTF("Recieved a message. \r\n");

  }

 }

}

---------------------------------------------------------------------------------------------------------------------------------

There is no such error in my code. everything is working fine. But, when I send the multicast message. Nothing is received. What I am doing wrong?

Kinds Regards,
Saad.