Shared I/O problem

[Etienne Fortin]

What kind of IO device? You have some who need to be blocked for a transfer
to finish so overlapping IO requests are not a problem. You have disk file.
You have any other kind of IO device. For sure, IO devices states is kept
for each thread. Well, I'm pretty sure of that. To the best of my knowledge,
this is how Linux or Windows or any other OS works.

Etienne





-----Message d'origine-----
De : willisfield [mailto:willisfield at 163.com] 
Envoyé : 16 mars, 2005 23:33
À : rtems-users at rtems.com
Objet : Shared I/O problem


	We know tasks can be preempted in RTEMS. If one task is using an io
device, at the same time the task is preempted by another task which will
use the io device. The state of the io device will be changed and when the
first task restarts, how to recover the state of the io device? that is to
say how to resolve the situation that one io device can be used between
different tasks of RTEMS?
	Thanks for your reading and any answer is appreatiated!