Subject: Re: Request for review
To: Andrew Doran <>
From: Bill Studenmund <>
List: tech-kern
Date: 09/23/2002 10:53:44
On Mon, 23 Sep 2002, Andrew Doran wrote:

> Bill Studenmund <> wrote:
> > Yes. Why does cs_ctl_chan == NULL turn stuff off?
> Because that would allow the 0th channel to stomp on the other channel's
> control lines, and give applications the misleading impression that they can
> change DTR/RTS. There again, given that those ports aren't ever likely to be
> used as ttys, it's not necessary.

Right; they are wired up for keyboard and mouse only.

Note that if they ever get ttys, you can use the cs_wr5_dtr and cs_wr5_rts
fields to indicate that those ttys DON'T have DTR & RTS pins. So all
should be well.

> > By requiring cs_ctl_chan be set, you ripple the consequences of this
> > change out to ALL the other drivers. If they can just leave it NULL,
> > no change needed.
> I was paranoid about expecting the whole structure to be initalized, since
> it seems that at one time at least one front-end didn't do that. Perhaps
> that's not a valid concern, I don't know for sure.

Hmmm... Then we should probably check all of them to make sure. :-(

> So, it looks good with those changes?

I think so.

Take care,