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# append(_:length:)

Appends to the receiver a given number of bytes from a given buffer.

```
func append(_ bytes: UnsafeRawPointer, length: Int)
```

## Parameters

`bytes`

A buffer containing data to append to the receiver’s content.

`length`

The number of bytes from `bytes` to append.

## Discussion

A sample using this method can be found in [Working With Mutable Binary Data](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/BinaryData/Tasks/WorkingMutableData.html#//apple_ref/doc/uid/20002150).

---

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