@unwrap_spec(family=int, type=int, proto=int,
                 w_fdobj=WrappedDefault(None))
    def descr_init(self, space, family=AF_INET, type=SOCK_STREAM, proto=0,
                   w_fdobj=None):
        try:
            if not space.is_w(w_fdobj, space.w_None):
                if _WIN32:
                    from rpython.rlib.rsocket import _c
                    # it is possible to pass some bytes representing a socket
                    # in the file descriptor object on winodws
                    info_charptr = rffi.str2charp(w_fdobj)
                    try:
                        info_ptr = rffi.cast(_c.WSAPROTOCOL_INFOW, info_charptr)
                        fd = _c.WSASocketW(_c.FROM_PROTOCOL_INFO, _c.FROM_PROTOCOL_INFO,
                        _c.FROM_PROTOCOL_INFO, info_ptr, 0, _c.WSA_FLAG_OVERLAPPED)
                        if fd == rsocket.INVALID_SOCKET:
                            raise converted_error(space, rsocket.last_error())
                        sock = RSocket(family, type, proto, fd)
                    finally:
                        lltype.free(info_charptr, flavor='raw')