B_UNIT
if ((dv = device_find_by_driver_unit(name, B_UNIT(bootdev))) != NULL) {
B_CONTROLLER(bootdev), B_UNIT(bootdev),
punit = B_UNIT(bootdev);
unit = B_UNIT(bootdev);
bunit = B_UNIT(bootdev);
bunit = B_UNIT(bootdev);
p[-1] = '0' + B_UNIT(dev);
booted_unit = B_UNIT(bootdev);
unit = B_UNIT(bootdev);
#define B_X68K_SCSI_ID(val) B_UNIT(val)
default_kernel[2] = '0' + B_UNIT(bootdev);
unit = B_UNIT(bootdev);
name_netif[255 - majdev], B_UNIT(bootdev));