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

    OpenVMS usage:longword_signed
    type:         longword integer (signed)
    access:       write only
    mechanism:    by value

    Field extracted by LIB$EXTV, sign-extended to a longword.