Stepping question..

Kevin Fisher kgf at
Mon Sep 25 10:45:14 UTC 2000

> You might try examining the IRCConnection and TelnetMachine classes, in
> particular the #processIO method. They both use stepping to moniter a
> socket.

Yes, this is where I originally got the idea of using step for such tasks. :)

> However, I don't think you'd want to use stepping to do low level io, for
> many reasons (including that stepping is tied, afaict, to the current
> project). Perhaps a peek at ConnectionQueue>>listenLoop would be more
> useful. The real key is to establish a Process of the right priority. You
> can use the (Delay forMilliseconds: 500) wait. idiom to get the timing
> right. You want to set the priority to be highIOPriority or lowIOPriority
> (see ProcessorScheduler).
> Hope this helps.

Thanks for the pointer, I'll take a look into the ConnectionQueue methods.  
After some experimentation with my 'step'-based polling I can see why it 
doesn't work so well for low-level I/O. :)   I figured there had to be a 
better way hidden somewhere...  The Task class also looks to fit my needs 
quite well too..

> Cheers,
> Bijan Parsia.
> On Sun, 24 Sep 2000, Kevin Fisher wrote:
> > 
> > Hmm, interesting...yes, this might help me.  I'm just writing a simple class 
> > to poll the serial port every 500ms or so.  I've been using the standard 
> > SerialPort class, but I'm wondering if  the 'flow' classes might be a better 
> > solution?  I've managed a roundabout way to poll the port using 'steps' right 
> > now..quite different from what I've done in pure C in UNIX...
> > 
> > > 
> > > Does this Task class help?  SUnit test requires SUnit 2.6+.  It is
> > > tricky to write to the Transcript from background processes, but John
> > > Chludzinski's recent fix will help you.
> > > 
> > > Rob
> > 
> > [attachment snipped!]
> > 
> > 
> > 

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