Attaches a buffer of opaque data that is distributed by Built-in Topics during discovery.
- Entity:
- dds::domain::DomainParticipant, dds::sub::DataReader, dds::pub::DataWriter
- Properties:
- RxO = NO;
Changeable = YES
- See also
- dds::sub::builtin_subscriber
Usage
The purpose of this QoS is to allow the application to attach additional information to the created dds::core::Entity objects, so that when a remote application discovers their existence, it can access that information and use it for its own purposes. This information is not used by RTI Connext.
One possible use of this QoS is to attach security credentials or some other information that can be used by the remote application to authenticate the source.
In combination with operations such as dds::domain::DomainParticipant::ignore(const dds::domain::DomainParticipant & participant, const dds::core::InstanceHandle & handle), dds::pub::ignore, dds::sub::ignore, and dds::topic::ignore(), this QoS policy can assist an application to define and enforce its own security policies.
The use of this QoS is not limited to security; it offers a simple, yet flexible extensibility mechanism.
Important: RTI Connext stores the data placed in this policy in pre-allocated pools. It is therefore necessary to configure RTI Connext with the maximum size of the data that will be stored in policies of this type. This size is configured with rti::core::policy::DomainParticipantResourceLimits::participant_user_data_max_length, rti::core::policy::DomainParticipantResourceLimits::writer_user_data_max_length, and rti::core::policy::DomainParticipantResourceLimits::reader_user_data_max_length.