You can invoke DEC DATATRIEVE from DCL command level with the
   DATATRIEVE DCL command. The DCL DATATRIEVE command lets
   you specify options to customize your DEC DATATRIEVE session.

   You can abbreviate the DCL DATATRIEVE command to the
   shortest form that is unique among other DCL commands.

   The DATATRIEVE command has the following format:

     DATATRIEVE  [qualifier [...]]  ["dtr-command-string"]