consume_uint8t
buffer_cursor = consume_uint8t(buf, &len, &operation);
*buf = consume_uint8t(*buf, len, &selector);
*buf = consume_uint8t(*buf, len, &selector);
*buf = consume_uint8t(*buf, len, &selector);
*buf = consume_uint8t(*buf, len, &selector);
*buf = consume_uint8t(*buf, len, &selector);
buffer_cursor = consume_uint8t(buf, &len, &operation);