---
title: createMutableRawSpan()
framework: fskit
role: symbol
role_heading: Instance Method
path: fskit/fsmutablefiledatabuffer/createmutablerawspan()
---

# createMutableRawSpan()

Return a MutableRawSpan to the underlying bytes of the data buffer.

## Declaration

```swift
func createMutableRawSpan() throws -> MutableRawSpan
```