Subject: Re: pppd's cdtrcts option is broken!
To: Bill Studenmund <>
From: Frederick Bruckman <>
List: current-users
Date: 09/04/1998 14:48:52
On Fri, 4 Sep 1998, Bill Studenmund wrote:

> On Fri, 4 Sep 1998, Frederick Bruckman wrote:
> > I'm getting this message after building userland from Sep. 3's sup: 
> > 
> > /usr/sbin/pppd: In file /etc/ppp/options: unrecognized option 'cdtrcts'

> You should still send the pr! :-)

Done! (bin/6102)

> What options do you have on the /etc/ttys line for tty00? I didn't think
> that chat asserted crtscts...

I have tty00 turned off in /etc/ttys.

I was surprised at first, too. Upon reflection, I think it may in fact be
desirable for chat to work that way. AFAIK, all modems >=28,800 power up
with hardware handshaking enabled. The point is not worth pressing, since
it's practically impossible to overflow your buffers while the modem is in
command mode.

In fact, I've found that you can take a mac68k box (with its goofy serial
port), a "hardware handshaking" cable (that ties DTR to RTS), and set up
pppd with 'crtscts', practically oblivious to the problem. Since "DTR off"
typically isn't sensed for .05 to .06 seconds (settable via S25), the
modem doesn't actually hang up except on long file transfers.