Common Driver Model for RTAI

[Gilles Chanteperdrix]

Jan Kiszka wrote:
 > [off-topic] Shared memory between kernel und user space POSIX 
 > applications? What more beyond the existing mmap will be needed? To 
 > setup shm between fusion processes, standard mmap already works, there 
 > is nothing special in my eyes.

Kernel-space and user-space have to share the same namespace for
shm_open. There are two ways to do this, one is to have an RTAI-only
namespace, and to implement an mmap for user-space pretty much the same
way as rt_heap_bind for the native skin.


 > > You said that each driver has a set of non-rt entry points. So, I
 > > imagined, but I may be wrong, that these entry points are use to map
 > > usual Linux device file descriptors to RTDM drivers. Now the question
 > > was about how this mapping was done.
 > > 
 > 
 > The non-rt entry points are not mapped to the standard Linux namespace. 
 > You are just free (as far as the driver supports it) to call the RTDM 
 > API also from non-rt contexts. Tthat's all. No magic here.

But if I understood correctly, the RTDM API is the same as the standard
API. You mean that there is an RTDM version of "select" which can not
sleep on standard file descriptors ?


-- 


					    Gilles Chanteperdrix.