On a directory, the sticky permission prevents users from renaming, moving or deleting contained files owned by users other than themselves, even if they have write permission to the directory.
Absolute form The other way to use the chmod command is the absolute form, in which you specify a set of three numbers that together determine all the access classes and types.
There are three Classes — Owner, Group, Others. Distinct permissions apply to members of the file's group. You may also like to see shredplease see Chapter 7 lsattr list attributes. This will list if whether a file has any special attributes as set by chattr.
For a directory, this means that you can only add files to it, but not rename or delete any existing file.
Use the -R option to change files recursively, chattr has a large number of attributes which can be set on a file, read the manual page for further information. When setgid is applied to a directory, new files and directories created under that directory will inherit their group from that directory.
Distinct permissions apply to others. This permission must be set for executable programs, in order to allow the operating system to run them.
This is interesting because it really works.