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# getBoundStreams(withBufferSize:inputStream:outputStream:)

Creates and returns by reference a bound pair of input and output streams.

```
class func getBoundStreams(withBufferSize bufferSize: Int, inputStream: AutoreleasingUnsafeMutablePointer<InputStream?>?, outputStream: AutoreleasingUnsafeMutablePointer<OutputStream?>?)
```

## Parameters

`bufferSize`

The size of the buffer, in bytes, used to transfer data from `inputStream` to `outputStream`.

`inputStream`

On return, contains an input stream.

`outputStream`

On return, contains an output stream.

## Discussion

The created streams are bound to one another, such that any data written to `outputStream` is received by `inputStream`.

This is a convenience method for calling <doc://com.apple.documentation/documentation/CoreFoundation/CFStreamCreateBoundPair(_:_:_:_:)> and bridging from the returned Core Foundation types.

## See Also

  <doc://com.apple.documentation/documentation/CoreFoundation/CFStreamCreateBoundPair(_:_:_:_:)>


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