1. A method in a computer system for sharing a file stored at another computer system, the method comprising: receiving from the other computer system a notification that the file is to be shared with the computer system, the notification including metadata of the file; creating a virtual file using a file system of the computer system; storing the metadata of the file in association with the virtual file; and after the file is changed at the other computer system, receiving from the other computer system metadata for the file and updating the metadata stored in association with the virtual file based on the received metadata.