another, rtems vs rest?

[Joel Sherrill]

"J.Saravanan" wrote:
> 
> Hi,
> 
> Well, I've a beginners question (in rtos world).

Well since I haven't seen a reply yet, I'll take a quick swing.

> I understand RTEMS is an RTOS and is most suitable for control
> applications. It can be seen that (from mailing list archive) RTEMS can
> also be used for non-RTOS purpose, with a small shell and few applications
> that are statically linked.

Yes.
 
> My question is, If time is not critical then what prevents from using
> RTEMS as general purpose OS, just like linux. I believe, one cannot link
> too may applications in an RTOS like in general purpose OS. Is that
> correct? Then what is the knee point?

Right now, the lack of dynamic loading is the biggest lacking for
usefulness.  There has been work on a dynamic loader but I don't
know the precise status of it at the moment.

The lack of memory protection is a liability but there have
certanly been plenty of general purpose OSes without that.
 
> (Assuming RTEMS and the rest has all the facilities available, like
> library, etc.)

It has programming libraries but is lacking in graphics
and device driver support in comparison to GNU/Linux.
If you were constructing a PDA based upon RTEMS that would
be OK, since you would settle on a single graphics
standard and hardware configuration but desktop computing
is way too varied.

> Thanks,
> 
> Regards,
> -Saran

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
   Support Available             (256) 722-9985