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# toMemory()

Creates and returns an initialized output stream that will write stream data to memory.

```
class func toMemory() -> Self
```

## Return Value

An initialized output stream that will write stream data to memory.

## Discussion

The stream must be opened before it can be used.

You retrieve the contents of the memory stream by sending the message [`property(forKey:)`](/documentation/Foundation/Stream/property(forKey:)) to the receiver with an argument of `NSStreamDataWrittenToMemoryStreamKey`.

## See Also

[`outputStreamToBuffer:capacity:`](/documentation/Foundation/NSOutputStream/outputStreamToBuffer:capacity:)

Creates and returns an initialized output stream that can write to a provided buffer.

  [Stream Programming Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Streams/Streams.html#//apple_ref/doc/uid/10000188i)

[`outputStreamToFileAtPath:append:`](/documentation/Foundation/NSOutputStream/outputStreamToFileAtPath:append:)

Creates and returns an initialized output stream for writing to a specified file.


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