DDS_SubscriptionMatchedStatus Struct Reference
[DataReaders]

DDS_SUBSCRIPTION_MATCHED_STATUS More...


Data Fields

DDS_Long total_count
 The total cumulative number of times the concerned DDS_DataReader discovered a "match" with a DDS_DataWriter.
DDS_Long total_count_change
 The change in total_count since the last time the listener was called or the status was read.
DDS_Long current_count
 The current number of writers with which the DDS_DataReader is matched.
DDS_Long current_count_peak
 <<eXtension>> The highest value that current_count has reached until now.
DDS_Long current_count_change
 The change in current_count since the last time the listener was called or the status was read.
DDS_InstanceHandle_t last_publication_handle
 A handle to the last DDS_DataWriter that caused the status to change.


Detailed Description

DDS_SUBSCRIPTION_MATCHED_STATUS

A "match" happens when the DDS_DataReader finds a DDS_DataWriter for the same DDS_Topic with an offered QoS that is compatible with that requested by the DDS_DataReader.

This status is also changed (and the listener, if any, called) when a match is ended. A local DDS_DataReader will become "unmatched" from a remote DDS_DataWriter when that DDS_DataWriter goes away for any reason.

Examples:

HelloWorld_subscriber.c.


Field Documentation

The total cumulative number of times the concerned DDS_DataReader discovered a "match" with a DDS_DataWriter.

This number increases whenever a new match is discovered. It does not change when an existing match goes away.

The change in total_count since the last time the listener was called or the status was read.

The current number of writers with which the DDS_DataReader is matched.

This number increases when a new match is discovered and decreases when an existing match goes away.

<<eXtension>> The highest value that current_count has reached until now.

The change in current_count since the last time the listener was called or the status was read.

A handle to the last DDS_DataWriter that caused the status to change.


RTI Data Distribution Service C API Version 4.5e Copyright © 23 Oct 2011 Real-Time Innovations, Inc