In the following procedure, a user changes permissions on a file that the user owns.
% chmod who operator permissions filename
Specifies whose permissions are to be changed.
Specifies the operation to be performed.
Specifies what permissions are to be changed. For the list of valid symbols, see Figure 5, Table 5, Setting File Permissions in Symbolic Mode.
Specifies the file or directory.
% ls -l filename
In the following example, the owner removes read permission others.
% chmod o-r example-file1
the following example, the owner adds read and execute permissions for user, group, and others.
% chmod a+rx example-file2
In the following example, the owner adds read, write, and execute permissions for group members.
% chmod g=rwx example-file3