---
title: "CFRunLoopStop(_:)"
framework: corefoundation
role: symbol
role_heading: Function
path: "corefoundation/cfrunloopstop(_:)"
---

# CFRunLoopStop(_:)

Forces a CFRunLoop object to stop running.

## Declaration

```swift
func CFRunLoopStop(_ rl: CFRunLoop!)
```

## Parameters

- `rl`: The run loop to stop.

## Discussion

Discussion This function forces rl to stop running and return control to the function that called CFRunLoopRun() or CFRunLoopRunInMode(_:_:_:) for the current run loop activation. If the run loop is nested with a callout from one activation starting another activation running, only the innermost activation is exited.

## See Also

### Starting and Stopping a Run Loop

- [CFRunLoopRun()](corefoundation/cfrunlooprun().md)
- [CFRunLoopRunInMode(_:_:_:)](corefoundation/cfrunloopruninmode(_:_:_:).md)
- [CFRunLoopWakeUp(_:)](corefoundation/cfrunloopwakeup(_:).md)
- [CFRunLoopIsWaiting(_:)](corefoundation/cfrunloopiswaiting(_:).md)