System, method and computer program product for multi-level file-sharing by concurrent users

Abstract

A method of accessing a shareable computer file includes receiving a request to access the shareable computer file, retrieving a file ID from a stub file corresponding to the shareable computer file, retrieving a file name from a database corresponding to the file ID, accessing the shareable computer file if a user has not modified the shareable computer file, and accessing a modified copy of the shareable file stored in the stub file if the user has modified the shareable computer file. A database is generated in operating system space or accessed using the operating system, and includes file IDs and their corresponding file names for shareable computer files. The stub file is generated locally to correspond to the shareable computer file, and includes a modified copy of the shareable computer file if the shareable computer file has been modified, and a link to the shareable computer file if the shareable computer file has not been modified. If the shareable computer file has not been modified, a read-only operation retrieves any of file contents, file position and file size from the shareable computer file. File attributes relating to the shareable computer file can be retrieved from the stub file. The database is provided by the operating system for use by a Virtual Private Server.