u_char *pkt;
        pkt = malloc(54);
/*.......................*/
      	destmac = (mac_address *)pkt_data;
	srcmac	= (mac_address *)(pkt_data + 6);
/*.......................*/
        memcpy( (void *)pkt, (void *)srcmac, 6 );
	memcpy( (void *)(pkt + 6), (void *)destmac, 6 );
	memcpy( (void *)(pkt + 12), &ip_tos, 2);
	memcpy( (void *)(pkt + 14), &ip_hd, 20 );
	memcpy( (void *)(pkt + 14 + sizeof(ip_hd)), &tcp_hd, 20);