---
title: "read(_:)"
framework: realitykit
role: symbol
role_heading: Instance Method
path: "realitykit/lowlevelbufferresource/read(_:)"
---

# read(_:)

Reads the buffer synchronously on the CPU. The buffer is only valid for the lifetime of the callback.

## Declaration

```swift
final func read<R, E>(_ body: (RawSpan) throws(E) -> R) throws(E) -> R where E : Error, R : ~Copyable
```

## Parameters

- `body`: A closure that receives a read-only span over the buffer’s bytes.

## Discussion

Discussion note: Any error thrown by body.

## See Also

### Reading buffer contents

- [read(commandBuffer:)](realitykit/lowlevelbufferresource/read(commandbuffer:).md)