Syntax:

      /SUBDICTIONARY = file-specification  path-name

  Use /SUBDICTIONARY to  change  the  file  specification  to  which  a
  subdictionary  directory points.  You set the directory to point to a
  VMS subdictionary file that you are moving or renaming.

  Use the standard VMS file specification.  You must include device and
  directory  names  for  the file.  You can use system logical names to
  define the device, the directory, and the file name.  You cannot  use
  group or process logical names.  The default file name is CDD.DIC.

  You can use a full or relative path name.  You cannot  use  wildcards
  in the path name.

  Use RENAME/SUBDICTIONARY to avoid having to  delete  a  subdictionary
  directory  before  you  create  a  new one pointing to the file's new
  location.  /SUBDICTIONARY both deletes the old  pointer  and  creates
  the new one.

  Before you reset the directory to point to the file, use the DCL COPY
  command to change the location of the subdictionary file.