CUSTOM_LISTENER
ASSERT_OK(verify_sockopt(client_fd, CUSTOM_LISTENER, "connect", 0), "verify_sockopt ener");
err += verify_sockopt(fd, CUSTOM_LISTENER, "listen", 1);
err += verify_sockopt(client_fd, CUSTOM_LISTENER, "accept", 0);
for (i = CUSTOM_INHERIT1; i <= CUSTOM_LISTENER; i++) {