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# CMMutableDataBlockBuffer.BlockSource

Provides ability to allocate memory for blocks using custom allocator

```
struct BlockSource
```

## Topics

### Initializers

[`init(allocate: (Int) -> UnsafeMutableRawBufferPointer, deallocate: (UnsafeMutableRawBufferPointer) -> Void)`](/documentation/CoreMedia/CMMutableDataBlockBuffer/BlockSource/init(allocate:deallocate:))

### Instance Properties

[`var allocate: (Int) -> UnsafeMutableRawBufferPointer`](/documentation/CoreMedia/CMMutableDataBlockBuffer/BlockSource/allocate)

[`var deallocate: (UnsafeMutableRawBufferPointer) -> Void`](/documentation/CoreMedia/CMMutableDataBlockBuffer/BlockSource/deallocate)

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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