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  "title" : "AccessoryFeatureRuntimeSession"
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# AccessoryFeatureRuntimeSession

A protocol that represents a feature session’s transport extension.

```
protocol AccessoryFeatureRuntimeSession : AnyObject, Sendable
```

## Overview

A feature runtime session is a counterpart to the data provider’s [`AccessoryFeatureSession`](/documentation/AccessoryTransportExtension/AccessoryFeatureSession) for worker features ([`AccessoryWorker`](/documentation/AccessoryTransportExtension/AccessoryWorker) and [`AccessoryGPUWorker`](/documentation/AccessoryTransportExtension/AccessoryGPUWorker)).

The framework supplies the types that conform to this protocol. Once your transport extension activates a session, the system delivers the session’s events to the [`AccessoryFeatureRuntimeSessionHandler`](/documentation/AccessoryTransportExtension/AccessoryFeatureRuntimeSessionHandler) you provide. Create a session with [`makeFeatureSession(_:)`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/makeFeatureSession(_:)) and then call [`activate()`](/documentation/AccessoryTransportExtension/AccessoryFeatureRuntimeSession/activate()) to start it.

## Topics

### Managing the session life cycle

[`func activate() async throws`](/documentation/AccessoryTransportExtension/AccessoryFeatureRuntimeSession/activate())

Registers the session and requests that the system start it.

[`func invalidate()`](/documentation/AccessoryTransportExtension/AccessoryFeatureRuntimeSession/invalidate())

Unregisters the session.

### Sending data

[`func send(data: Data) async throws`](/documentation/AccessoryTransportExtension/AccessoryFeatureRuntimeSession/send(data:))

Sends data to the data provider extension.

## Relationships

### Conforming Types

[`FeatureSession`](/documentation/AccessoryTransportExtension/AccessoryGPUWorker/FeatureSession)

[`FeatureSession`](/documentation/AccessoryTransportExtension/AccessoryWorker/FeatureSession)

### Inherits From

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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