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# CGDataProviderGetBytePointerCallback

A callback function that returns a generic pointer to the provider data.

```
typealias CGDataProviderGetBytePointerCallback = (UnsafeMutableRawPointer?) -> UnsafeRawPointer?
```

## Parameters

`info`

A generic pointer to private data shared among your callback functions. This is the same pointer you supplied to `CGDataProviderCreateDirectAccess`.

## Return Value

A generic pointer to your provider data. By suppling this pointer, you are giving Core Graphics read-only access to both the pointer and the underlying provider data. You must not move or modify the provider data until Core Graphics calls your [`CGDataProviderReleaseBytePointerCallback`](/documentation/CoreGraphics/CGDataProviderReleaseBytePointerCallback) function.

## Discussion

When Core Graphics needs direct access to your provider data, this function is called.

For information on how to associate your function with a direct-access data provider, see `CGDataProviderCreateDirectAccess` and `CGDataProviderDirectAccessCallbacks`.

---

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