routin

    OpenVMS usage:procedure
    type:         procedure value
    access:       call without stack unwinding
    mechanism:    by reference
    Routine to be executed while the process is in executive mode.
    The routin argument is the address of this routine.

 arglst

    OpenVMS usage:arg_list
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Argument list to be passed to the routine specified by the routin
    argument. The arglst argument is the address of this argument
    list.

    If the arglst value is nonzero and is not accessible as an
    address or if the routine is inaccessible, the service returns
    SS$_ACCVIO.

    Alpha and Integrity server systems require a pointer to a valid
    argument list or a value of 0 in the arglst argument. This means
    that the arglst argument must contain an accessible virtual
    address for an argument list, the first longword of which must
    be a valid list size.