VMS Help RTL Routines, OTS$, OTS$MULCx, Returns  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    OpenVMS usage:complex_number
    type:         D_floating complex, G_floating complex
    access:       write only
    mechanism:    by value

    Complex result of multiplying two complex numbers. OTS$MULCD_
    R3 returns a D-floating complex number. OTS$MULCG_R3 returns a
    G-floating complex number.