FSVolume.OpenCloseOperations
Methods and properties implemented by volumes that want to receive open and close calls for each item.
Declaration
protocol OpenCloseOperations : NSObjectProtocolOverview
When a file system volume conforms to this protocol, the kernel layer issues an open call to indicate desired access, and a close call to indicate what access to retain. A file is fully closed when the kernel layer issues a close call with no retained open nodes. When a file system receives the close call, it removes all access to the item. When all memory mappings to the item release, the kernel layer issues a final close.
If a file system volume doesn’t conform to this protocol, the kernel layer can skip making such calls to the volume.