As you learned in Chapter 4, “On the Internet,” there are three types of permissions: read, write, and execute (
x). For any file or directory, permissions are assigned to three categories: user, group, and other. This section focuses on group permissions. First, though, we want to highlight three commands used to change the group, user, or access permissions of a file or directory:
chgrp—Changes the group ownership of a file or directory
chown—Changes the owner of a file or directory
chmod—Changes the access permissions ...