VMS Help CMS, DELETE, HISTORY, Qualifiers, /OUTPUT[=file-specification]  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Directs CMS to write output to the specified file. If you omit the
    /OUTPUT qualifier (or if you specify /OUTPUT but do not provide a
    file specification), CMS creates a file named HISTORY.DMP in your
    current default directory.