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# NSData.ReadingOptions

Options for methods used to read data objects.

```
struct ReadingOptions
```

## Topics

### Initializers

[`init(rawValue:)`](/documentation/Foundation/NSData/ReadingOptions/init(rawValue:))

### Constants

[`mappedIfSafe`](/documentation/Foundation/NSData/ReadingOptions/mappedIfSafe)

A hint indicating the file should be mapped into virtual memory, if possible and safe.

[`uncached`](/documentation/Foundation/NSData/ReadingOptions/uncached)

A hint indicating the file should not be stored in the file-system caches.

[`alwaysMapped`](/documentation/Foundation/NSData/ReadingOptions/alwaysMapped)

Hint to map the file in if possible.

### Legacy Constants

[`dataReadingMapped`](/documentation/Foundation/NSData/ReadingOptions/dataReadingMapped)

Deprecated name for [`mappedIfSafe`](/documentation/Foundation/NSData/ReadingOptions/mappedIfSafe).

[`mappedRead`](/documentation/Foundation/NSData/ReadingOptions/mappedRead)

Deprecated name for [`dataReadingMapped`](/documentation/Foundation/NSData/ReadingOptions/dataReadingMapped).

[`uncachedRead`](/documentation/Foundation/NSData/ReadingOptions/uncachedRead)

Deprecated name for [`uncached`](/documentation/Foundation/NSData/ReadingOptions/uncached).


---

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