The access rights are provided to the users or groups of users to access a file. The following are the access rights that can be provided to a specific user for a specific file.
• None – This will not allow the user to learn the presence of the file. The users have very much lesser access to files. The files in the user directory are not allowed to be read by the user when obeying this restriction.
• Knowledge – Determination of existence of a file can be made. Also, the creator of the file or the owner of the file can also be determined. The petition to the creator to provide additional access rights can also be made possible by the user.
• Execution – The user is not allowed to copy the code or program. A program can be loaded and executed by the user. The accessibility is made with this restriction for the programs with ownership otherwise said to be proprietary programs.
• Reading – The user is allowed to read and copy the file for the execution. In certain cases, the files are not allowed to make a copy such that the user is only to view the contents of the files.
• Appending – The user is not allowed to modify the contents of the files such that data can be added only at the end of the file. Collection of data from many sources can be made possible with this access right.
• Updating – Modification, deletion, and the addition of data can be made possible with the files by the user.
• Changing protection – The access rights which are provided to other users can be changed only by the owner of the file. In certain cases, the owner will extend the rights to other users also.
• Deletion – It allows the user to delete the file which is stored in the system.
This is said to be the hierarchy such that if any particular user is allowed the appending right for a specific file, then that user also is granted the rights as follows: