Path names are unique designations that identify a dictionary
       directory or object in the dictionary hierarchy.

       The dictionary directory you are assigned as a DEC DATATRIEVE
       user is not a top level directory. CDD$TOP is the name of the
       top level directory in a DMU format dictionary; an anchor like
       MYNODE::SYS$COMMON:[CDDPLUS] is the name of a top level directory
       in a CDO format dictionary. You can trace the parentage of a
       directory or object by:

       o  Joining the given names of directories and objects starting
          with CDD$TOP or the anchor

       o  Including the given names of intermediate directories

       o  Ending with the given name of the target directory or object
          you want to specify

       This path you travel between CDD$TOP or the anchor and a target
       directory or object is called a path name.

       In path names, each given name starts with a letter (A-Z)
       and ends with a letter or digit (0-9). A given name cannot be
       longer than 31 characters and can contain only letters, digits,
       dollar signs ($), and underscores (_). Separate the names of the
       directories and objects in a path name with periods.

       When you start DEC DATATRIEVE, your default directory is set to
       the contents of the logical symbol CDD$DEFAULT. You can change
       your default directory by using the SET DICTIONARY command (see
       HELP SET).