Subject: Re: Out of pty's - help
To: Jukka Marin <email@example.com>
From: Michael L. Hitch <firstname.lastname@example.org>
Date: 10/10/1994 12:18:36
On Oct 9, 10:43pm, "Jukka Marin" wrote:
> I'm constantly running out of pty's (virtual terminal lines).
> I recompiled the kernel with pty set to 48 (and according to binpatch,
> the number really is 48). I created the device nodes pty[qrs]* and
> tty[qrs]* using MAKEDEV. I rebooted. Still, only the first 16 pty's
> are used by the system. When they run out, screen etc. refuses to work.
> What am I doing wrong?
That's hard to tell. I just configured a kernel with 32 pty's and
made the ptyq?/ttyq? devices. The version of screen I am running very
happily starts using the ttyq? devices, and when those are all used up,
it starts onthe ttyp? devices. I had much more than 16 pty devices in
use before I was unable to create a new process (which I would suspect
might be the max number of processes configured).
How is your version of screen configured to allocate pty devices?
I looked at the telnetd program, and it will look for ptyp?, then
ptyq?, all the way through "rstuvwxyzPQRST". It does give up if a stat
on /dev/tty?0 fails, so if /dev/ttyq0 didn't exist, telnetd would only
try to use 16 pty devices.
You could try "stty </dev/ttyq0" to see if the device is even
recognized. I just tried "stty </dev/ttypf", which was accepted
(although the process hung). I did "stty </dev/ttyq0" on a system that
had the device defined in /dev, but not configured into the kernel. It
returned "Device not configured" as expected. Doing that on the system
with 32 pty devices configured reacted the same way as /dev/ttypf did.
Michael L. Hitch INTERNET: email@example.com
Office of Systems and Computing Services
Montana State University Bozeman, MT USA