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# resumeData

Returns the resume data for a download that is not yet complete.

```
var resumeData: Data? { get }
```

## Return Value

The resume data for a download that is not yet complete. This data represents the necessary state information that an `NSURLDownload` object needs to resume a download. The resume data can later be used when initializing a download with [`init(resumeData:delegate:path:)`](/documentation/Foundation/NSURLDownload/init(resumeData:delegate:path:)). Returns `nil` if the download is not able to be resumed.

## Discussion

Resume data is returned only if both the protocol and the server support resuming. For details on how to resume a connection, see the documentation for [`init(resumeData:delegate:path:)`](/documentation/Foundation/NSURLDownload/init(resumeData:delegate:path:)).

---

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