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

    This function returns the current name for the specified socket
    descriptor. The name is a format specific to the address family
    (AF_INET) assigned to the socket.
    The bind() function, not the getsockname()  function, makes the
    association of the name to the socket.
    Related Functions
    See also bind() and socket().