The following reply was made to PR kern/32682; it has been noted by GNATS.

From: christos@zoulas.com (Christos Zoulas)
To: Hauke Fath <hf@spg.tu-darmstadt.de>
Cc: gnats-bugs@NetBSD.org, kern-bug-people@NetBSD.org,
	gnats-admin@NetBSD.org
Subject: Re: kern/32682: netbsd-3 ptyfs intermittent failure with Matlab
Date: Wed, 8 Feb 2006 12:35:08 -0500

 On Feb 8,  4:55pm, hf@spg.tu-darmstadt.de (Hauke Fath) wrote:
 -- Subject: Re: kern/32682: netbsd-3 ptyfs intermittent failure with Matlab
 
 | I finally managed to get hold of an error instance...
 | 
 | Ktracing Matlab 14 gave me
 | 
 | [tj@Katzenbuckel clpois]$ kdump | less
 | 
 | [...]
 | 
 |   25647 MATLAB   CALL  open(0xbac662e0,0x8002,0)
 |   25647 MATLAB   NAMI  "/emul/linux/dev/pts/5"
 |   25647 MATLAB   NAMI  "/dev/pts/5"
 |   25647 MATLAB   RET   open -1 errno -13 Permission denied
 | 
 | 
 | Am 31.01.2006 um 12:52 Uhr -0500 schrieb Christos Zoulas:
 | >Can you show what w(1) prints
 | 
 | Katzenbuckel# w
 |   1:20PM  up 6 days,  5:46, 1 user, load averages: 1.19, 1.49, 1.59
 | USER     TTY     FROM              LOGIN@  IDLE WHAT
 | tj       :0      -                Thu07AM     ? /bin/sh /usr/pkg/bin/startkde
 | 
 | >and the "interesting" ptys in /dev/[pt]ty??.
 | 
 | [tj@Katzenbuckel clpois]$ ll /dev/pts/
 | total 31
 | dr-xr-xr-x  1 root wheel   512 Feb  2 07:50 ./
 | drwxr-xr-x  5 root wheel 30720 Oct 23 03:27 ../
 | crw-rw-rw-  1 root wheel  3, 0 Oct 22 23:25 0
 | crw-rw-rw-  1 root wheel  3, 1 Feb  3 03:15 1
 | crw-rw-rw-  1 root wheel  3, 2 Feb  8 07:21 2
 | crw--w----  1 hf   tty    3, 3 Feb  2 11:28 3
 | crw-rw-rw-  1 root wheel  3, 4 Feb  8 09:39 4
 | 
 | >I suspect what is going on, is that you have a rogue program that is
 | >opening old style pty's behind the pty subsystem's back, so when ptyfs
 | >tries to open the same pty, it fails. So when it fails for pts/4 for
 | >example, what does lsof say for /dev/{t,p}typ4?
 | 
 | Is lsof tied to the OS version? I got a warning "...compiled for 
 | NetBSD 2" and no output.
 | 
 | fstat(1) gave me
 | 
 | Katzenbuckel# fstat /dev/ttyp5
 | USER     CMD          PID   FD MOUNT       INUM MODE         SZ|DV R/W NAME
 | root     fstat       8778    0 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     fstat       8778    1 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     fstat       8778    2 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     tcsh       19818   15 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     tcsh       19818   16 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     tcsh       19818   17 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     tcsh       19818   18 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | root     tcsh       19818   19 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | hf       tcsh       21122   15 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | hf       tcsh       21122   16 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | hf       tcsh       21122   17 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | hf       tcsh       21122   18 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | hf       tcsh       21122   19 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | tj       bash       24622    0 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | tj       bash       24622    1 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | tj       bash       24622    2 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | tj       bash       24622  255 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | tj       kdeinit      902   20 /        1855043 crw-rw-rw-   ttyp5 rw 
 | /dev/ttyp5
 | Katzenbuckel# fstat /dev/ptyp5
 | USER     CMD          PID   FD MOUNT       INUM MODE         SZ|DV R/W NAME
 | tj       kdeinit      902   19 /        1854014 crw-rw-rw-   ptyp5 rw 
 | /dev/ptyp5
 | 
 | 
 | -- The latter is kind of interesting. What confused me, though, is 
 | that after logging out and logging in again, Matlab did still fail 
 | but an fstat for the relevant {p,t}typ? came up empty.
 | 
 | As a further data point, a coworker who uses Gnome exclusively claims 
 | he has never seen the error (most of the people here use KDE). ISTR, 
 | though, that I have seen Matlab fail under XFCE4 - which is set up to 
 | start the KDE and Gnome daemons. Hmmm...
 | 
 | Anything else that I could check?
 | 
 | 	hauke
 
 This is great information. Now what application opened the pty? kde terminal?
 This is the application that is not using openpty and it is trying to open
 pty's directly.
 
 christos