FD_NEED_TWADDLE_BIT
set_bit(FD_NEED_TWADDLE_BIT,
clear_bit(FD_NEED_TWADDLE_BIT,
test_bit(FD_NEED_TWADDLE_BIT, &drive_state[current_drive].flags)) &&
if (test_bit(FD_NEED_TWADDLE_BIT, &drive_state[current_drive].flags))
#define FD_NEED_TWADDLE (1 << FD_NEED_TWADDLE_BIT)