---
title: IOServiceMatchingCallback
framework: iokit
role: symbol
role_heading: Type Alias
path: iokit/ioservicematchingcallback
---

# IOServiceMatchingCallback

Callback function to be notified of IOService publication.

## Declaration

```swift
typealias IOServiceMatchingCallback = (UnsafeMutableRawPointer?, io_iterator_t) -> Void
```

## Parameters

- `refcon`: The refcon passed when the notification was installed.
- `iterator`: The notification iterator which now has new objects.

## See Also

### Callbacks

- [IOAsyncCallback](iokit/ioasynccallback.md)
- [IOAsyncCallback0](iokit/ioasynccallback0.md)
- [IOAsyncCallback1](iokit/ioasynccallback1.md)
- [IOAsyncCallback2](iokit/ioasynccallback2.md)
- [IOServiceInterestCallback](iokit/ioserviceinterestcallback.md)