1 CDIRECTORY
  Syntax: CDIRECTORY dirname
  where   dirname  is the directory name

  Sets the current HBOOK directory name to `dirname'. Note  that the HCDIR
  command is executed immediately, whereas it is only executed when you do
  `FETCH', `LDIR', `ZDIR' or `SHOW  DIR' after a `SET DIR' command.
  You should therefore always use `SET DIR' before a `FETCH' command.

  Note that the  directory name  should not be  preceded by a '/'. However
  '//' is allowed so you can go to the top level. You can use either
!^
  '\' or '..' to go up a directory level.
!$\backslash$ or '..' to go up a directory level.

  Note that the Mn_Fit HBOOK file top level directory name is `//MN_HBIN'.

