/sys$common/syshlp/helplib.hlb ALLOCATE, Qualifiers, /LOG  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /LOG (default)
       /NOLOG

    Displays a message indicating the name of the device allocated.
    If the operation specifies a logical name that is currently
    assigned to another device, then the superseded value is
    displayed.