В отговор на:

---

If a user has write permission on a directory he can rename and remove files on that directory even if those files not belong to him. How can we prevent this? The owner of a directory can set the directory's "sticky bit", octal value 1000, which will give the rename and remove permissions of any file in that directory to the fileowner, the directory owner, and the superuser (in this order).

If you examine your / directory using the command ls -l, you will notice your /tmp directory has the sticky bit on.


drwxrwxrwt 4 root root 50176 Apr 20 04:50 tmp/
This allow different users to use this directory for temporary files, when only the file owner can delete his files (the directory owner for /tmp is the root user and he can also delete files). This prevents other users from deleting temporary files created by others and harming their work.

---