VMS Help CONVERT, file, Qualifiers, /APPEND  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Controls whether converted records from an input file are
    appended to an existing sequential file.

    Format

      /APPEND

      /NOAPPEND  (DEFAULT)

    The /APPEND qualifier is useful when you want to convert an
    existing file to the format of an existing output file and append
    the converted records to the existing output file.

    If you specify the /APPEND qualifier and the /CREATE qualifier,
    /APPEND overrides the /CREATE.

    You should use this option when you are loading records into
    a sequential file that already contains records, or when you
    are creating a new sequential file. When the output file is a
    direct access file (relative or indexed), the /APPEND qualifier
    is ignored.