<!--
{
  "availability" : [
    "macOS: 27.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Virtualization",
  "identifier" : "/documentation/Virtualization/VZVirtioQueueElement/writeBuffer(_:exactLength:)",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Method",
  "symbol" : {
    "kind" : "Instance Method",
    "modules" : [
      "Virtualization"
    ],
    "preciseIdentifier" : "c:objc(cs)VZVirtioQueueElement(im)writeBuffer:exactLength:error:"
  },
  "title" : "writeBuffer(_:exactLength:)"
}
-->

# writeBuffer(_:exactLength:)

Writes to the memory represented by the pointer to the buffer you provide to the write buffers.

```
func writeBuffer(_ buffer: UnsafeMutableRawPointer, exactLength: Int) throws
```

## Parameters

`buffer`

A pointer to the memory containing the data to write to the write buffers.

`exactLength`

The number of bytes the framework should write to the write buffers.

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)