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TYPESUPPORT QosPolicy (DDS Extension)

This policy can be used to modify the code generated by RTI Code Generator so that the [de]serialization routines act differently depending on the information passed in via the object pointer. This policy also determines if padding bytes are set to zero during serialization.

It includes the members in .



Field Name


void *


Value to pass into the type plug-in's serialization/deserialization function. See Note below.



Determines whether or not the padding bytes will be set to zero during CDR serialization.

For a DomainParticipant: Configures how padding bytes are set when serializing data for the builtin topic DataWriters and DataReaders.

For DataWriters and DataReaders: Configures how padding bytes are set when serializing data for that entity.

May be:

  • ZERO_CDR_PADDING (Padding bytes will be set to zero during CDR serialization)

  • NOT_SET_CDR_PADDING (Padding bytes will not be set to any value during CDR serialization)

  • AUTO_CDR_PADDING (For a DomainParticipant, the default behavior is NOT_SET_CDR_PADDING. For a DataWriter or DataReader, the behavior is to inherit the value from the DomainParticipant.)

Note: RTI generally recommends that you treat generated source files as compiler outputs (analogous to object files) and that you do not modify them. RTI cannot support user changes to generated source files. Furthermore, such changes would make upgrading to newer versions of Connext DDS more difficult, as this generated code is considered to be a part of the middleware implementation and consequently does change from version to version. The plugin_data field in this QoS policy should be considered a back door, only to be used after careful design consideration, testing, and consultation with your RTI representative.


This QoS policy may be modified after the DataWriter or DataReader is enabled.

It can be set differently for the DataWriter and DataReader.

Related QoS Policies


Applicable Entities

System Resource Considerations


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