public void send ()
    {
        
        int nbytes = 0;
        ByteBuffer dummy = ByteBuffer.allocate(1);
        dummy.limit(1);

        while (true) {
            try {
                nbytes = w.write(dummy);
            } catch (IOException e) {
                throw new ZError.IOException(e);
            }
            if (nbytes == 0) {
                continue;
            }
            wcursor.incrementAndGet();
            assert (nbytes == 1);
            break;
        }
    }