Some questions with NetFSMountURLAsync?

I am working on a OS X app which mount server volumes through NetFSMountURLAsync. And now I have many questions.

• When I successfully mounting a volume from server and I want to check if the share always available. Then I close the share, but I can still check it's online through NSFileManager's mountedVolumeURLsIncludingResourceValuesForKeys: options:. Afterwards I use getResourceValue: forKey: error: to retrieve volumename by NSURLVolumeNameKey so I can get offline status if there is not volume name exists, but it is still not quick enough. How to get status change immediately?

• When I just mount and unmount a volume repeatly, I found the memory keep increasing even I stop any operations it still keep high memory and not release. I use ARC and no other operations. At the same time, NetAuthSysAgent's memory also keep increasing, Any ideas?

• And last when it takes long time to mount I use NetFSMountURLCancel to cancel a mount, but sometimes it just hang there and do not terminate. How's that happens?

via Chebli Mohamed