---
title: cancelWriting()
framework: avfoundation
role: symbol
role_heading: Instance Method
path: avfoundation/avassetwriter/cancelwriting()
---

# cancelWriting()

Cancels the creation of the output file.

## Declaration

```swift
func cancelWriting()
```

## Discussion

Discussion If the asset writer is in AVAssetWriter.Status.failed or AVAssetWriter.Status.completed state, calling this method has no effect. Otherwise, invoking it blocks the calling thread until the asset writer finishes canceling the writing session. If the asset writer created an output file during the writing process, calling this method deletes the file.

## See Also

### Managing writing sessions

- [start()](avfoundation/avassetwriter/start().md)
- [startWriting()](avfoundation/avassetwriter/startwriting().md)
- [startSession(atSourceTime:)](avfoundation/avassetwriter/startsession(atsourcetime:).md)
- [endSession(atSourceTime:)](avfoundation/avassetwriter/endsession(atsourcetime:).md)
- [finishWriting(completionHandler:)](avfoundation/avassetwriter/finishwriting(completionhandler:).md)
- [finishWriting()](avfoundation/avassetwriter/finishwriting().md)