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# CFReadStreamCopyError(_:)

Returns the error associated with a stream.

```
func CFReadStreamCopyError(_ stream: CFReadStream!) -> CFError!
```

## Parameters

`stream`

The stream to examine.

## Return Value

A CFError object that describes the current problem with stream, or `NULL` if there is no error. Ownership follows the [The Create Rule](https://developer.apple.com/library/archive/documentation/CoreFoundation/Conceptual/CFMemoryMgmt/Concepts/Ownership.html#//apple_ref/doc/uid/20001148-103029).

## Discussion

---

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