VMS Help TCPIP Services, Programming Interfaces, Sockets API, inet_network(), Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    This function returns an internet network address as local host
    integer value when an ASCII string representing the address
    in the internet standard dotted-decimal format is given as its
    argument.
                                   NOTE
       The 64-bit return from OpenVMS Alpha systems has zero-
       extended bits in the high 32 bits of R0.