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# getBytes(_:length:)

Copies a number of bytes from the start of the data object into a given buffer.

```
func getBytes(_ buffer: UnsafeMutableRawPointer, length: Int)
```

## Parameters

`buffer`

A buffer into which to copy data.

`length`

The number of bytes from the start of the receiver’s data to copy to `buffer`.

## Discussion

The number of bytes copied is the smaller of the `length` parameter and the [`length`](/documentation/Foundation/NSData/length) of the data encapsulated in the object.

## See Also

[`description`](/documentation/Foundation/NSData/description)

A string that contains a hexadecimal representation of the data object’s contents in a property list format.


---

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