ANSI Common Lisp 20 Files 20.1 File System Concepts
Many file systems permit more than one filename to designate
a particular file.
Even where multiple names are possible, most file systems have a convention
for generating a canonical filename in such situations. Such a canonical
filename (or the pathname representing such a filename) is
called a truename.
The truename of a file may differ from other filenames
for the file because of
logical device translations in the file system,
logical pathname translations within Common Lisp,
or other artifacts of the file system.
The truename for a file is often, but not necessarily, unique for
each file. For instance, a Unix file with multiple hard links
could have several truenames.
188.8.131.52 Examples of Truenames