VMS Help DTM, SHOW, TEST_DESCRIPTION, Command Qualifiers, /OUTPUT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

   /OUTPUT[=file-specification]

   Sends the requested information to a specified file. If you
   specify the file name but omit the file type, the file type
   defaults to .LIS. By default, the output is sent to SYS$OUTPUT.