T-floating-point-base
    OpenVMS usage:floating_point
    type:         IEEE T_floating
    access:       read only
    mechanism:    by value
    Base. The T-floating-point-base argument is an IEEE T-floating
    number containing the base.
 longword-integer-exponent
    OpenVMS usage:longword_signed
    type:         longword (signed)
    access:       read only
    mechanism:    by value
    Exponent. The longword-integer-exponent argument is a signed
    longword that contains the longword exponent.