chmod 444 — what r--r--r-- means

When to use 444

Locking a file as read-only for all, such as a reference document or a config you want to protect from accidental edits. The owner must chmod it back to write to it again.

Set it with chmod

Apply this permission to a file:

chmod 444 filename

Or apply it recursively to a directory and everything inside it:

chmod -R 444 directory/

Other common permissions

• chmod 777 rwxrwxrwx
• chmod 755 rwxr-xr-x
• chmod 644 rw-r--r--
• chmod 700 rwx------
• chmod 600 rw-------
• chmod 640 rw-r-----

Or build any permission with the interactive chmod calculator.