The SampleInfo structure contains information associated with each sample. More...

Data Fields
DDS_SampleStateKind	sample_state
	The associated data sample has/has not been read previously. More...

DDS_ViewStateKind	view_state
	Associated instance has/has not been seen before. More...

DDS_InstanceStateKind	instance_state
	Indicates whether the associated instance currently exists. instance_state can be one of: DDS_ALIVE_INSTANCE_STATE DDS_NOT_ALIVE_DISPOSED_INSTANCE_STATE DDS_NOT_ALIVE_NO_WRITERS_INSTANCE_STATE Can use DDS_NOT_ALIVE_INSTANCE_STATE as a test for either 'NOT_ALIVE' state. For example. More...

DDS_Time_t	source_timestamp
	The time provided by the DataWriter when the sample was written.

DDS_Time_t	reception_timestamp
	The time the sample was received by the DataReader.

DDS_InstanceHandle_t	instance_handle
	The handle that locally identifies the associated instance.

DDS_InstanceHandle_t	publication_handle
	The local handle of the source DataWriter.

int	disposed_generation_count
	The number of times the instance has become 'ALIVE' after being explicitly disposed. (Computed at the time the sample arrives at the DataReader.)

int	no_writers_generation_count
	The number of times the instance has become 'ALIVE' after being automatically disposed due to no active writers. (Computed at the time the sample arrives at the DataReader.)

int	sample_rank
	Number of samples related to this instance that follow in the collection returned by the DataReader read or take operations.

int	generation_rank
	The generation difference of this sample and the most recent sample in the collection. More...

int	absolute_generation_rank
	The generation difference between this sample and the most recent sample. More...

unsigned char	valid_data
	Set to true (non-zero) if the associated DataSample contains data. More...

Detailed Description

The SampleInfo structure contains information associated with each sample.

Field Documentation

◆ absolute_generation_rank

int DDS_SampleInfo::absolute_generation_rank

The generation difference between this sample and the most recent sample.

The absolute_generation_rank indicates the generation difference (ie, the number of times the instance was disposed and became alive again) between this sample, and the most recent sample (possibly not in the returned collection) of this instance.

◆ generation_rank

int DDS_SampleInfo::generation_rank

The generation difference of this sample and the most recent sample in the collection.

generation_rank indicates the generation difference (ie, the number of times the instance was disposed and became alive again) between this sample, and the most recent sample in the collection related to this instance.

◆ instance_state

DDS_InstanceStateKind DDS_SampleInfo::instance_state

Indicates whether the associated instance currently exists. instance_state can be one of:
DDS_ALIVE_INSTANCE_STATE
DDS_NOT_ALIVE_DISPOSED_INSTANCE_STATE
DDS_NOT_ALIVE_NO_WRITERS_INSTANCE_STATE

Can use DDS_NOT_ALIVE_INSTANCE_STATE as a test for either 'NOT_ALIVE' state. For example.

if (sample_info->view_state & DDS_NOT_ALIVE_INSTANCE_STATE) ...

◆ sample_state

DDS_SampleStateKind DDS_SampleInfo::sample_state

The associated data sample has/has not been read previously.

sample_state indicates whether or not the DataReader has previously read the associated sample.
One of:
DDS_READ_SAMPLE_STATE
DDS_NOT_READ_SAMPLE_STATE.

Use DDS_ANY_SAMPLE_STATE to test for either state.

◆ valid_data

unsigned char DDS_SampleInfo::valid_data

Set to true (non-zero) if the associated DataSample contains data.

The associated DataSample may not contain data if it this sample indicates a change in sample state (for example ALIVE -> DISPOSED).

◆ view_state

DDS_ViewStateKind DDS_SampleInfo::view_state

Associated instance has/has not been seen before.

view_state indicates whether the DataReader has already seen samples for the most current generation of the related instance.
view_state can be one of:
DDS_NEW_VIEW_STATE
DDS_NOT_NEW_VIEW_STATE

Data Fields