3.4. Configure UDP Transport

You may need to configure the UDP transport component that is pre-registered by RTI Connext DDS Micro. To change the properties of the UDP transport, first the UDP component has be unregistered, then the properties have to be updated, and finally the component must be re-registered with the updated properties.

Example code:

• Unregister the pre-registered UDP component:

  /* Unregister the pre-registered UDP component */
  if (!RT_Registry_unregister(registry, "_udp", NULL, NULL))
  {
      /* failure */
  }
  

• Configure UDP transport properties:

  struct UDP_InterfaceFactoryProperty *udp_property = NULL;
  
  udp_property = (struct UDP_InterfaceFactoryProperty *)
      malloc(sizeof(struct UDP_InterfaceFactoryProperty));
  if (udp_property != NULL)
  {
      *udp_property = UDP_INTERFACE_FACTORY_PROPERTY_DEFAULT;
  
      /* allow_interface: Names of network interfaces allowed to send/receive.
       * Allow one loopback (lo) and one NIC (eth0).
       */
      REDA_StringSeq_set_maximum(&udp_property->allow_interface,2);
      REDA_StringSeq_set_length(&udp_property->allow_interface,2);
  
      *REDA_StringSeq_get_reference(&udp_property->allow_interface,0) = DDS_String_dup("lo");
      *REDA_StringSeq_get_reference(&udp_property->allow_interface,1) = DDS_String_dup("eth0");
  }
  else
  {
      /* failure */
  }
  

• Re-register UDP component with updated properties:

  if (!RT_Registry_register(registry, "_udp",
                       UDP_InterfaceFactory_get_interface(),
                      (struct RT_ComponentFactoryProperty*)udp_property, NULL))
  {
      /* failure */
  }
  

For more details, see the Transports section in the User’s Manual.