fdc_sense_int
if (fdc_sense_int(fdc, &st0, &cyl) == FD_NOT_VALID)
if (fdc_sense_int(fdc, &st0, &cyl) == FD_NOT_VALID)
fdc_sense_int(fdc, NULL, NULL);
if (fdc_sense_int(fdc, &st0, NULL) == 0 &&
fdc_sense_int(fdc, &st0, &cyl);
if (fdc_sense_int(fdc, &st0, &cyl) == FD_NOT_VALID)
if (fdc_sense_int(fdc, &st0, &cyl) == FD_NOT_VALID)