Participant Use Cases
[Programming How-To's]

Working with domain partcipants. More... Working with domain participants.

Turning off auto-enable of newly created participant(s)

• Get the factory

• Change the value of the ENTITY_FACTORY for the DDS_DomainParticipantFactory

      struct DDS_DomainParticipantFactoryQos factory_qos = DDS_DomainParticipantFactoryQos_INITIALIZER;
  
      if (DDS_DomainParticipantFactory_get_qos(factory, &factory_qos)
                  != DDS_RETCODE_OK) {
          printf("***Error: failed to get domain participant factory qos\n");
      }
  
      /* Change the QosPolicy to create disabled participants */
      factory_qos.entity_factory.autoenable_created_entities = DDS_BOOLEAN_FALSE;
  
      if (DDS_DomainParticipantFactory_set_qos(factory,  &factory_qos) 
                             != DDS_RETCODE_OK) {
          printf("***Error: failed to set domain participant factory qos\n");
      }   
      
      DDS_DomainParticipantFactoryQos_finalize(&factory_qos);    
  

Getting the factory

• Get the DDS_DomainParticipantFactory instance:

    DDS_DomainParticipantFactory* factory = NULL; 
  
    factory = DDS_DomainParticipantFactory_get_instance();
  
    if (factory == NULL) { 
        printf("***Error: failed to get domain participant factory\n");
    }    
  

Setting up a participant

• Get the factory

• Create DDS_DomainParticipant:

      struct DDS_DomainParticipantQos participant_qos =
          DDS_DomainParticipantQos_INITIALIZER;
      DDS_DomainParticipant* participant;
      struct DDS_DomainParticipantListener participant_listener = 
          DDS_DomainParticipantListener_INITIALIZER;
      DDS_ReturnCode_t retcode;
  
      /* Set the initial peers. These list all the computers the application
         may communicate with along with the maximum number of RTI Data
         Distribution Service participants that can concurrently run on that
         computer. This list only needs to be a superset of the actual list of
         computers and participants that will be running at any time.
      */         
      const char* NDDS_DISCOVERY_INITIAL_PEERS[] = {
          "host1",
          "10.10.30.192",
          "1@localhost",        
          "2@host2",
          "my://", /* all unicast addresses on transport plugins with alias "my" */
          "2@shmem://", /* shared memory */
          "FF00:ABCD::0",
          "sf://0/0/R", /* StarFabric transport plugin */
          "1@FF00:0:1234::0",
          "225.1.2.3",
          "3@225.1.0.55",
          "FAA0::0#0/0/R",              
      };
      const long NDDS_DISCOVERY_INITIAL_PEERS_LENGTH =
                   sizeof(NDDS_DISCOVERY_INITIAL_PEERS)/sizeof(const char*);
                   
      /* MyDomainParticipantListener_* functions are user defined to match
         DDS_DomainParticipantListener functions */
      participant_listener.as_topiclistener.on_inconsistent_topic = 
          MyDomainParticipantListener_InconsistentTopic;
      participant_listener.as_publisherlistener.as_datawriterlistener.on_offered_deadline_missed =
          MyDomainParticipantListener_OfferedDeadlineMissed;
      participant_listener.as_publisherlistener.as_datawriterlistener.on_offered_incompatible_qos = 
          MyDomainParticipantListener_OfferedIncompatibleQos;
      participant_listener.as_publisherlistener.as_datawriterlistener.on_liveliness_lost = 
          MyDomainParticipantListener_LivelinessLost;
      participant_listener.as_publisherlistener.as_datawriterlistener.on_publication_matched = 
          MyDomainParticipantListener_PublicationMatch;
      participant_listener.as_subscriberlistener.on_data_on_readers = 
          MyDomainParticipantListener_DataOnReaders;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_requested_deadline_missed = 
          MyDomainParticipantListener_RequestedDeadlineMissed;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_requested_incompatible_qos = 
          MyDomainParticipantListener_RequestedIncompatibleQos;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_sample_rejected = 
          MyDomainParticipantListener_SampleRejected;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_liveliness_changed = 
          MyDomainParticipantListener_LivelinessChanged;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_data_available = 
          MyDomainParticipantListener_DataAvailable;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_subscription_matched = 
          MyDomainParticipantListener_SubscriptionMatched;
      participant_listener.as_subscriberlistener.as_datareaderlistener.on_sample_lost =  
          MyDomainParticipantListener_SampleLost;
  
      /* initialize participant_qos with default values */
      retcode = DDS_DomainParticipantFactory_get_default_participant_qos(factory, 
                                                               &participant_qos);
      if (retcode != DDS_RETCODE_OK) {
          printf("***Error: failed to get default participant qos\n");
      }
      if (!DDS_StringSeq_from_array(&participant_qos.discovery.initial_peers,
                               NDDS_DISCOVERY_INITIAL_PEERS,
                               NDDS_DISCOVERY_INITIAL_PEERS_LENGTH)) {
          printf("***Error: failed to set discovery.initial_peers qos\n");
      }
                                       
      /* Create the participant */
      participant = 
          DDS_DomainParticipantFactory_create_participant(factory, 
                                                          domain_id, 
                                                          &participant_qos, 
                              &participant_listener /* or NULL */,
                                                          DDS_STATUS_MASK_ALL); 
  
       if (participant == NULL) {
          printf("***Error: failed to create domain participant\n");
      }
  
      return participant;
  

Tearing down a participant

• Get the factory

• Delete DDS_DomainParticipant:

      DDS_ReturnCode_t retcode;
  
      retcode = DDS_DomainParticipantFactory_delete_participant(
          factory, participant);
  
      if (retcode != DDS_RETCODE_OK) {
          printf("***Error: failed to delete domain participant\n");
      }