BSD socket Udp multicast

Hello,

do anyone have experience with BSD socket? I am using LPC1788. What i want to do is to receive a string or data from certain IpAddress with its port.
I want to receive data from two IP-Adress and Port-Number separately:
IP: 239,127.0.1 Port 60001
IP: 239,127.0.2 Port 60002
Look at the code example:

uint8_t uni_ip1[IP4_ADDR_LEN] = {192,168,50,73};
uint8_t mcast_ip1[IP4_ADDR_LEN] = {239,127,0,1};
uint8_t mcast_ip2[IP4_ADDR_LEN] = {239,127,0,2};
void bsd_thread(void const *arg)
{
        SOCKADDR_IN addr;
        SOCKADDR_IN addr2;
        SOCKADDR_IN recaddr;

        int sock,res,addrlen;
        int sock2;
        int bind_status;
        int port_num=1001;
        char dbuf[200];
        char sendebuf[10] = "HELLO";
        sock = socket(AF_INET,SOCK_DGRAM,0);
        printf("sock_status = %i \n", sock);
        addr.sin_port        = htons(port_num);
        addr.sin_family      = PF_INET;

        addr.sin_addr.s_b1 = uni_ip1[0];
        addr.sin_addr.s_b2 = uni_ip1[1];
        addr.sin_addr.s_b3 = uni_ip1[2];
        addr.sin_addr.s_b4 = uni_ip1[3];

        bind_status = bind (sock, (SOCKADDR *)&addr, sizeof(addr));
        printf("bind_status = %i \n", bind_status);

        //Here i start to bind multicast adress with port
        sock2 = socket(AF_INET,SOCK_DGRAM,0);
        printf("sock_status2 = %i \n", sock);
        addr2.sin_port        = htons(60001);
        addr2.sin_family      = PF_INET;

        addr2.sin_addr.s_b1 = mcast_ip1[0];
        addr2.sin_addr.s_b2 = mcast_ip1[1];
        addr2.sin_addr.s_b3 = mcast_ip1[2];
        addr2.sin_addr.s_b4 = mcast_ip1[3];

        bind_status = bind (sock2, (SOCKADDR *)&addr2, sizeof(addr2));
        printf("bind_status2 = %i \n", bind_status);
        printf("addr2.sin_port = %i \r\n",ntohs(addr2.sin_port));
        printf("addr2[%i . %i . %i . %i], \n",addr2.sin_addr.s_b1,addr2.sin_addr.s_b2,addr2.sin_addr.s_b3,addr2.sin_addr.s_b4);

        /*Here i join into 2 multicast adresse*/
        igmp_join(0,mcast_ip1);
        igmp_join(0,mcast_ip2);

        while(1)
        {

                while(1)
                {
                        addrlen = sizeof (addr);
                        res = recvfrom (sock, dbuf, sizeof (dbuf), MSG_DONTWAIT , (SOCKADDR *)&recaddr, &addrlen);
                        printf("recvfrom = %i \r\n", res);
                        if(res >0 )
                        {
                                printf("receive good \r\n");
                                printf("%s\n",dbuf);
                                printf("recvfrom = %i \r\n", res);
                        }

                        res = sendto (sock, (char *)&sendebuf, strlen(sendebuf), 0, (SOCKADDR *)&addr, sizeof (addr));
                        printf("sendto = %i \r\n", res);
                        if (res > 0)
                        {
                                printf("send good \r\n");
                        }
                        osDelay (100);
                        printf("\n");
                        break;
                }
        }
}
#define BSDTHREAD_STACKSIZE (1024)
osThreadDef (bsd_thread, osPriorityNormal , 1, BSDTHREAD_STACKSIZE);

to receive from both IP-Multicastaddress, i used the function:
igmp_join(0,mcast_ip1);
igmp_join(0,mcast_ip2);

The problem is, i receive data from both IP_adress with the port-Number 60001 and it doesn't matter which IP-Adress i used to send data.

Can anyone help how can i get the data only from specific IP-Adress and PORT-Number, Which the Data are sent to.
Thank you for help

Best Regards