rtapi_io(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 and the kernel space implementation of rtapi_ioperm always succeeds)

Call from init/cleanup code and from realtime tasks. These functions will cause illegal instruction exceptions in non-realtime components, as well as in uspace rtapi_app when it is not setuid root.

As in Linux.

inb(3), inw(3), inl(3), outb(3), outw(3), outl(3), ioperm(3)

Jeff Epler