How to change File Permission ? chmod
chmod is used to change the permissions of files or directories. On Linux and other Unix-like operating systems, there is a set of rules for each file which defines who can access that file, and how they can access it. These rules are called file permissions or file modes. The command name chmod stands for "change mode", and it is used to define the way a file can be accessed. Before continuing, you should read the section What Are File Permissions, And How Do They Work? in our documentation of the umask command. It contains a comprehensive description of how to define and express file permissions. In general, chmod commands take the form: chmod options permissions file name If no options are specified, chmod modifies the permissions of the file specified by file name to the permissions specified by permissions. permissions defines the permissions for the owner of the file (the "user"), members of the group who owns the file (the "group"), ...