VMS Help DECTPU, TPU$MESSAGE, Returns  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    OpenVMS usage:cond_value
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value

    Longword condition value.

                                   NOTE

       The return status should be ignored because it is intended
       for use by the $PUTMSG system service.