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# init(header:addr:size:value:trailer:)

Creates a new I/O notifier message with the parameters you provide.

```
init(header: mach_msg_header_t, addr: UInt64, size: UInt64, value: UInt64, trailer: mach_msg_trailer_t)
```

## Parameters

`header`

The Mach message header.

`addr`

The address of the I/O write.

`size`

The size of the value written.

`value`

The value written to `addr`.

`trailer`

The Mach message trailer.

---

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