The key in a file attribute dictionary whose value indicates the identifier for the device on which the file resides.
The corresponding value is an NSNumber object containing an unsigned long.
Available in Mac OS X v10.0 and later.
Declaration Syntax Version Information- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)