Library /sys$common/syshlp/LSE$CLIHELP.HLB

1 /READ_ONLY

    Specifies that files in the indicated directories are read-only
    and unmodifiable by default. The /READ_ONLY qualifier prevents the
    WRITE command from writing files to the indicated directory unless
    you subsequently override this default.

2 /WRITE

       /WRITE (D)

    Specifies that files in the indicated directories are writeable
    and unmodifiable by default.