---
title: IODispatchSourceCancelHandler
framework: driverkit
role: symbol
role_heading: Type Alias
path: driverkit/iodispatchsourcecancelhandler
---

# IODispatchSourceCancelHandler

A block to execute when a canceled dispatch source stops executing tasks.

## Declaration

```occ
typedef void (^)(void) IODispatchSourceCancelHandler;
```

## See Also

### Starting and Stopping the Interrupt Source

- [SetEnableWithCompletion](driverkit/iointerruptdispatchsource/setenablewithcompletion.md)
- [Cancel](driverkit/iointerruptdispatchsource/cancel.md)