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# CFAllocatorAllocateCallBack

A prototype for a function callback that allocates memory of a requested size.

```
typealias CFAllocatorAllocateCallBack = (CFIndex, CFOptionFlags, UnsafeMutableRawPointer?) -> UnsafeMutableRawPointer?
```

## Parameters

`allocSize`

This function allocates a block of memory of at least `allocSize` bytes (always greater than 0).

`hint`

A bitfield that is currently not used (always set to 0).

`info`

An untyped pointer to program-defined data. Allocate memory for the data and assign a pointer to it. This data is often control information for the allocator. It may be `NULL`.

## Return Value

A pointer to the start of the block.

## Discussion

---

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