---
title: AudioOutputUnitStartProc
framework: audiotoolbox
role: symbol
role_heading: Type Alias
path: audiotoolbox/audiooutputunitstartproc
---

# AudioOutputUnitStartProc

## Declaration

```swift
typealias AudioOutputUnitStartProc = (UnsafeMutableRawPointer) -> OSStatus
```

## See Also

### Starting and Stopping Output

- [AudioOutputUnitStart(_:)](audiotoolbox/audiooutputunitstart(_:).md)
- [AudioOutputUnitStop(_:)](audiotoolbox/audiooutputunitstop(_:).md)
- [AudioOutputUnitStopProc](audiotoolbox/audiooutputunitstopproc.md)