---
title: "withUnsafeBlockRegions(_:)"
framework: coremedia
role: symbol
role_heading: Instance Method
path: "coremedia/cmmutabledatablockbuffer/withunsafeblockregions(_:)"
---

# withUnsafeBlockRegions(_:)

Access the potentially non-contiguous memory region referenced by this block buffer.

## Declaration

```swift
func withUnsafeBlockRegions<R>(_ body: ([CMReadOnlyDataBlockBuffer.BlockRegion]) throws -> sending R) rethrows -> sending R
```