       readdir ?-hidden? dirPath
              Returns  a  list  containing  the  contents  of the
              directory dirPath.  The directory entries  "."  and
              ".." are not returned.
              On  MS  Windows  systems,  -hidden  maybe specified
              include hidden files in the result.  This  flag  is
              ignored on Unix systems.

              This command is provided by Extended Tcl.
