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# Byte Order

Recognize constants that specify a byte-order format.

## Discussion

These constants are returned by [`NSHostByteOrder()`](/documentation/Foundation/NSHostByteOrder()).

## Topics

### Constants

[`var NS_BigEndian: Int`](/documentation/Foundation/NS_BigEndian)

The byte order is big endian.

[`var NS_LittleEndian: Int`](/documentation/Foundation/NS_LittleEndian)

The byte order is little endian.

[`var NS_UnknownByteOrder: Int`](/documentation/Foundation/NS_UnknownByteOrder)

The byte order is unknown.


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