---
title: "writeAttributeOctetString(withValue:completionHandler:)"
framework: matter
role: symbol
role_heading: Instance Method
path: "matter/mtrbaseclustertestcluster/writeattributeoctetstring(withvalue:completionhandler:)"
---

# writeAttributeOctetString(withValue:completionHandler:)

## Declaration

```swift
func writeAttributeOctetString(withValue value: Data, completionHandler: @escaping @Sendable ((any Error)?) -> Void)
```

```swift
func writeAttributeOctetString(withValue value: Data) async throws
```