Permission notation (rwxrwxrwx) in Linux CLI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the permission notation rwxr-xr-- mean?

It means the owner can read, write, and execute; the group can read and execute; others can only read.

beginner

What does each letter in rwxrwxrwx represent?

• r: read permission
• w: write permission
• x: execute permission

Repeated for owner, group, and others in that order.

beginner

How many permission sets are shown in rwxrwxrwx and who do they belong to?

There are three sets: owner (first 3 letters), group (middle 3 letters), and others (last 3 letters).

beginner

What does a dash - mean in permission notation like rw-r--r--?

A dash means that the permission is not granted. For example, - in place of x means no execute permission.

intermediate

How can you change file permissions using symbolic notation in Linux?

Use the chmod command with symbols like u (owner), g (group), o (others), and +, -, = to add, remove, or set permissions.

In rwxr-xr--, what permission does the group have?

A Write only

B Read, write, and execute

C Read and execute

D No permissions

The group has r-x which means read and execute permissions.

What does the x permission allow a user to do?

A Delete the file

B Write to the file

C Read the file

D Execute the file or enter the directory

The execute permission allows running a file as a program or entering a directory.

If a file has permissions rw-r--r--, who can write to it?

A Owner only

B Group only

C Others only

D Everyone

Only the owner has write permission indicated by w in the first set.

What does the first character in a long permission string like -rwxr-xr-x indicate?

A Owner permission

B File type (e.g., file or directory)

C Group permission

D Others permission

The first character shows the file type: - for file, d for directory.

Which command changes permissions using numeric notation?

A chmod 755 filename

B ls -l filename

C cat filename

D pwd

chmod 755 filename sets permissions using numeric notation.

Explain the meaning of the permission string rwxr-xr-- in simple terms.

Break it down into three groups of three letters.

Describe how you would change a file to allow only the owner to write, but everyone to read and execute.

Think about symbolic or numeric notation for permissions.