funcref := get_accept4Addr()
	if funcptrtest(GetZosLibVec()+SYS___ACCEPT4_A<<4, "") == 0 {
		*funcref = impl_accept4
	} else {
		*funcref = error_accept4
	}
	return (*funcref)(s, rsa, addrlen, flags)
}

func error_accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error) {
	fd = -1
	err = ENOSYS
	return
}