rtapi_device(3)

In kernel space, each rtapi_xxx or RTAPI_XXX identifier is mapped to the underlying kernel functionality, if available.

In userspace, or in kernels where the underlying functionality is not provided by a kernel, generally another implementation—possibly with reduced functionality—is provided. (For example, the userspace implementation for rtapi_device_register always succeeds)

Typically, these functions may be called from realtime init/cleanup code.

As in Linux.