Hi Achobanov,
you are right. In the described case, events from the instance of the virtual file system provider are delivered only for the user associated with this instance of the virtual file system provider.
To be precise.
1) When the association between the virtual file system instance and the user is 1:1, and the user makes a change on the file system, then the registered event handler is called and Session.CurrentSession.User property contains the user associated with the virtual file system instance. This user is each time the same user who initiated the operation on the virtual file system and who is the 'owner ' of the virtual file system instance.
2) When the association between the virtual file system instance and users is 1:n. In other words, when the SAME (reference equals) virtual file system is shared between users, and ANY user associated with this instance makes a change on the virtual file system, then the registered event handler is called and Session.CurrentSession.User property contains a user who initiated the operation on the virtual file system.
I hope that the explanation makes sense.