A key in the userinfo dictionary in a NSFileHandleReadCompletionNotification and NSFileHandleReadToEndOfFileCompletionNotification.
The corresponding value is an NSData object containing the available data read from a socket connection.
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)