VMS Help DTM, REVIEW, Review Subsystem, SPAWN, Command Qualifiers, /PROMPT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

   /PROMPT[=string]

   Specifies the DCL-prompt string for the subprocess. The default is
   to copy the current prompt string from the parent process. If you
   specify /PROMPT but do not specify a string, the default prompt is
   displayed.