RHEL Linux - Red Hat System Administration Practice Exam

What does the command 'chmod 755' accomplish?

1. Grants read, write, and execute permissions to the user; read and execute for group and others

2. Grants only read permission for all users

3. Removes all permissions from group and others

4. Grants write and execute permissions to the group only

The correct answer is: Grants read, write, and execute permissions to the user; read and execute for group and others

The command 'chmod 755' is used to set the permissions of a file or directory in a Linux system. When executed, it modifies the permissions in a specific manner. The number '755' is composed of three digits, each of which defines permissions for different categories of users: the owner (user), the group, and others. In this instance, the first digit '7' corresponds to the owner's permissions. The value '7' is a combination of read (4), write (2), and execute (1) permissions, which means the owner has full control over the file or directory—able to read, write, and execute it. The second digit '5' pertains to the group's permissions. The value '5' is a combination of read (4) and execute (1) permissions only—meaning that the group can read and execute the file or directory, but cannot modify it. The third digit '5' defines the permissions for others (everyone else). Like the group, others have read and execute (but not write) permissions. Thus, the command effectively grants read, write, and execute permissions to the user; read and execute permissions to both the group and others. This structure is particularly useful for scripts or programs