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

       /DELETE
       /NODELETE

    Controls whether COPY deletes existing files of the same name
    during the copy operation. This qualifier is valid for RT-
    11 output only; it is equivalent to the RT-11 COPY command
    qualifier /REPLACE. In fact, you can use the EXCHANGE COPY
    command qualifier /REPLACE to control file deletion, although
    its function differs from that of /DELETE (see the description of
    the /REPLACE qualifier for details on its function).

    If you want a message displayed when you delete a file, include
    the /LOG qualifier in your command. To prevent automatic file
    deletion, use /NODELETE.

    The default is /DELETE. Files with the same name as the output
    file name are deleted after the new file has been copied.