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# startRunning()

Starts the flow of data through the capture pipeline.

```
func startRunning()
```

## Discussion

Call this method to start the flow of data from the capture session’s inputs to its outputs. This method is synchronous and blocks until the session starts running or it fails, which it reports by posting an [`runtimeErrorNotification`](/documentation/AVFoundation/AVCaptureSession/runtimeErrorNotification) notification.

---

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