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# handleMachMessage(_:)

Process an incoming Mach message.

```
optional func handleMachMessage(_ msg: UnsafeMutableRawPointer)
```

## Parameters

`msg`

A pointer to a Mach message, cast as a pointer to void.

## Discussion

The delegate should interpret this data as a pointer to a Mach message beginning with a msg_header_t structure and should handle the message appropriately.

The delegate should implement either `handleMachMessage:` or the [`PortDelegate`](/documentation/Foundation/PortDelegate) protocol method handlePortMessage:.

## See Also

  [Distributed Objects Programming Topics](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/DistrObjects/DistrObjects.html#//apple_ref/doc/uid/10000102i)


---

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