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# CFReadStreamHasBytesAvailable(_:)

Returns a Boolean value that indicates whether a readable stream has data that can be read without blocking.

```
func CFReadStreamHasBytesAvailable(_ stream: CFReadStream!) -> Bool
```

## Parameters

`stream`

The stream to examine.

## Return Value

`TRUE` if data can be read from `stream` without blocking, otherwise `FALSE`. If `stream` cannot tell if data is available without actually trying to read the data, this function returns `TRUE`.

## Discussion

---

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