Re: orocos core documentation

On Wed, 8 Oct 2003, Peter Soetens wrote:

[...]
> >  From this, my understanding is that during development LXRT can be used
> > to develop and debug, but ultimately the final product should be
> > compiled into a kernel module.
> 
> This is only true if your application is not using _any_ userspace library, 
> not even libc ...
> 
> >
> > Has the /RTAI-wind/ made this document redundant, or is your suggested
> > use of LXRT just another approach?
> 
> As you guessed, that paper is a bit outdated. The general consensus is now 
> that most realtime applications can and will run under LXRT, and never go to 
> kernel space. This is simply explained by the fact that no complex 
> application can run in the kernel because of the absence of libraries. 

Indeed. Real-time under Linux started with the implicit assumption
that "real-time == kernel space".
This ``equality'' is false (at least _in principle_): the fact
that a task runs in real-time has, in principle, nothing to do with
the CPU protection layer it runs in.
But, of course, _in practice_, many user space drivers and libraries
are not "real-time safe", in the sense that they use
non-deterministically blocking programming primitives.

Herman
-- 
  K.U.Leuven, Mechanical Engineering, Robotics Research Group
<http://people.mech.kuleuven.ac.be/~bruyninc> Tel: +32 16 322480