Hard link
Del info de las coreutils:
A "hard link" is another name for an existing file; the link and the
original are indistinguishable. Technically speaking, they share the
same inode, and the inode contains all the information about a
file--indeed, it is not incorrect to say that the inode _is_ the file.
On all existing implementations, you cannot make a hard link to a
directory, and hard links cannot cross file system boundaries. (These
restrictions are not mandated by POSIX, however.)
Nada que ver con borrar directorios, pero rompiendo cosas se aprende. Por suerte, quedan muchas cosas que romper, y muchas puestas de sol para ver.