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# holoscan::DataEntry

> Entry for data queue (may have metadata only, no tensor content).

Entry for data queue (may have metadata only, no tensor content).

```cpp showLineNumbers={false}
#include <holoscan/async_data_logger.hpp>
```

---

## Constructors

### DataEntry \[#dataentry]

#### Default

inline

```cpp showLineNumbers={false}
holoscan::DataEntry::DataEntry()
```

#### Overload 2

```cpp showLineNumbers={false}
holoscan::DataEntry::DataEntry(
    std::any data_arg,
    const std::string &id,
    int64_t acq_time,
    int64_t emit_time,
    IOSpec::IOType io_type,
    std::shared_ptr<MetadataDictionary> meta = nullptr,
    std::optional<cudaStream_t> stream = std::nullopt,
    std::any source_owner = {}
)
```

#### Overload 3

```cpp showLineNumbers={false}
holoscan::DataEntry::DataEntry(
    std::shared_ptr<holoscan::Tensor> tensor,
    const std::string &id,
    int64_t acq_time,
    int64_t emit_time,
    IOSpec::IOType io_type,
    std::shared_ptr<MetadataDictionary> meta = nullptr,
    std::optional<cudaStream_t> stream = std::nullopt
)
```

#### Overload 4

```cpp showLineNumbers={false}
holoscan::DataEntry::DataEntry(
    holoscan::TensorMap tensor_map,
    const std::string &id,
    int64_t acq_time,
    int64_t emit_time,
    IOSpec::IOType io_type,
    std::shared_ptr<MetadataDictionary> meta = nullptr,
    std::optional<cudaStream_t> stream = std::nullopt
)
```

---

## Types

### Type

| Name            | Value | Description |
| --------------- | ----- | ----------- |
| `Generic`       |       |             |
| `TensorData`    |       |             |
| `TensorMapData` |       |             |

---

## Member variables

| Name                    | Type                                                                                 | Description                                |
| ----------------------- | ------------------------------------------------------------------------------------ | ------------------------------------------ |
| `type`                  | `Type`                                                                               |                                            |
| `unique_id`             | `std::string`                                                                        |                                            |
| `acquisition_timestamp` | `int64_t`                                                                            | externally specified acquisition timestamp |
| `emit_timestamp`        | `int64_t`                                                                            | time when emit (or receive) was called     |
| `io_type`               | `IOSpec::IOType`                                                                     |                                            |
| `metadata`              | `std::shared_ptr< MetadataDictionary >`                                              |                                            |
| `stream`                | `std::optional< cudaStream_t >`                                                      | optional CUDA stream for GPU operations    |
| `data`                  | `std::variant< std::any, std::shared_ptr< holoscan::Tensor >, holoscan::TensorMap >` |                                            |
| `source_owner`          | `std::any`                                                                           |                                            |