The
Vt devclass
object has two main functions in the system.
The first is to manage
the allocation of unit numbers for device instances and the second is
to hold the list of device drivers for a particular bus type.
Each
Vt devclass
has a name and there cannot be two devclasses with the same name.
This ensures that unique unit numbers are allocated to device
instances.
Beware that this means
Vt devclass
must be the same for different bus attachments of the same device driver.
