[okl4-developer] An IPC driver for Wombat

[Nelson Tam]

On 13/02/2008, at 13:01, Geoff White wrote:

> Greetz,
>
> I'd like to write an IPC driver for Wombat, what I mean by that is a  
> way to send L4 IPC messages from the *NIX domain.
> I'm doing this mostly to learn about writing device drivers in  
> general and to provide a base to write tools that will help in  
> debugging native mode L4 process communication (when the time comes).
>
> The question that I have is what do you think the best abstraction  
> to use is?
> Should I create a char driver, a block device or a network driver?
> Obviously char drivers are the easiest, but I would think a network  
> driver would be the more natural and logical expression.
> Has anyone at OKLabs done this? How did you go about it?
>
> I'm really looking for ideas and challenge, not necessarily working  
> code.

Hi Geoff,

If all you'd like to do is learn about native L4 communication, is it  
possible
for you to utilise IPC between Iguana-level programs that are not  
Wombat?  For
example, take a look at the various example applications in iguana/ 
examples/.

If all you want to do is learn about L4 IPC, I highly recommend  
starting with
those, because IPC'ing between these processes is relatively  
straightforward.
In Wombat, the semantics could get a bit complicated which will  
distract you
from learning the actual IPC mechanism.

But to really answer your question, no one at OK has written a driver
specifically to do L4 IPC.  I would recommend using the char driver  
abstraction.

Hope you learn and have fun at the same time!

Nelson.