DataReader

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rgs
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Modern c++ interface: How to lookup a topic and create DataReader from PublicationBuiltinTopicData

Hi all,

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Are data samples queued and if so, where?

My understanding is that DDS DataWriters communicate CacheChanges to the HistoryCaches of the associated RTPS Writer. This CacheChange is then propagated to the mapped RTPS Readers before notifying their associated DDS DataReaders.

From the above statement, there are queues (the HistoryCache) on the RTPS Writers and Readers.

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rgs
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How to create a DataReader for DCPSParticipant in Python

Hello,

Environment:
debian 11 linux x64
python 3.9.2
rti_connext_dds-6.1.0

 

I'm using the Python api with rti, but it's not well documented or much example code:
How do I create a DataReadear to builtin topics, eg: DCPSParticipant.

I've tried the code below but it crashes when it tries to execute the bind_listener() call (see below).

Any help would be appreciated.
Thanks,

 

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Subscriber freed and restarted : no data received

Hello,

In my project, I need sometimes to destroy a subscriber and all its related datareaders, to instanciate them again after with the same parameters, without changing anything with participant.

The environment is .NET 4.0 / RTI DDS 5.1.0

Here is the sequence :

---subscriber intialization---

sub = participant.create_subscriber(SubQos, ...);

...

DataReader reader = sub.create_datareader_with_profile(SomeContentFilteredTopic, ..., DDS.StatusMask.STATUS_MASK_ALL);

...

reader.enable();

sub.begin_access();

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Modern C++11 Listener Example

I've been working on implementing a modern listener for a DataReader in C++11 and it's causing me issues.  The examples are all C++03 that I can see.

Can anyone point me to an example that uses a Modern C++11 listener? I'm mostly interested in the class that I need to inherit from the template dds::sub::DataReaderListener<T> along with it's overrides and then calling set_listener on the data reader.

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Publish and Subscribe on the same Topic, prevent catching own data

Hi,

My application needs to write and read on the same "TopicA". It works fine, but I don't want to catch data from my own dataWriter. Is there a way (QoS or ReadCondition) to prevent fire data to myself?

ReadCondition would be the best because I do not have the full control of the QoS, but I can't figure out how to deal with it.

Regars

JB 

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DataReaderListener not called

Hi,

I have successfully set up a publisher in a Java application, and its data is received by another participant. Registering the same participant that is publishing the data as a subscriber seems to be successful, too, but it seems my DataReaderListener is never called when something is published on the topic. Here's the code that is setting up the subscriber:

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Cannot Create Data Reader for New Topic

I'm working with an existing system which already has many topics. I've added a new one and I'm receiving the following error when attempting to create a data reader for the new topic:

PRESPsService_createLocalEndpoint:!assert pres psReader
DDS_DataReader_createI:!create reader
DDS_Subscriber_create_datareader_disabledI:!create reader
DDSDataReader_impl::create_disabledI:!create reader
DDSDataReader_impl::createI:!create reader
DDSDomainParticipant_impl::create_datareader:ERROR: Failed to create datareader

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How can I get a notification when my DataReader receives a ‘dispose’ sample with identity

Scenario:

I have UI application hosted on the remote machine. Server publishes data and UI Application(Remote) subscribe it continuously and populate data on UI.
If the server added a new record and published new data this data get subscribe through the UI application and populate on UI.

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sending only fields that have changed

Hi,

 

We are using RHEL7.5 and RTI DDS 5.3.1.

I've done some searching already.  I was wondering if it was possible for a datawriter to only send the fields that have changed in a message and a datareader to only act on those 'changed' fields.  Am I correct that this feature does not exist in RTI DDS currently?

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