/ERROR=EXIT
       /ERROR=CONTINUE (default)

    Determines if EFI$CP will continue processing or exit when an
    error occurs in during the copy. The default is to continue
    execution.

    When executing a set of commands from a procedure, it can be
    useful to exit EFI$CP when an error occurs. The /ERROR=EXIT
    qualifier will cause this to happen.

    In addition, two global DCL symbols will be created (if not
    already existant) that will contain the source and target
    filenames that failed:

    EFICP$COPY_SOURCE will contain the name of the input file

    EFICP$COPY_TARGET will contain the name of the output file