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# DADiskPeekCallback

Type of the callback function used by DARegisterDiskPeekCallback().

```
typealias DADiskPeekCallback = (DADisk, UnsafeMutableRawPointer?) -> Void
```

## Parameters

`disk`

A disk object.

`context`

The user-defined context parameter given to the registration function.

## Discussion

The peek callback functions are called in a specific order, from lowest order to highest order. DADiskClaim() could be used here to claim the disk object and DADiskSetOptions() could be used here to set up options on the disk object.

---

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