VMS Help EXCHANGE, COPY, Qualifiers, /SYSTEM  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /SYSTEM
       /NOSYSTEM

    Controls whether the COPY command copies files that have the file
    type SYS. Files with a file type of SYS are usually necessary for
    the operation of an RT-11 system. Only RT-11 volumes handle SYS
    files in this manner.

    The default is /NOSYSTEM; the COPY command does not copy an
    RT-11 file with the type SYS, whether matched by a wildcard
    specification or explicitly named. EXCHANGE displays a message
    whenever it skips over a SYS file during a copy operation.