bin/40813: bad ps/ptyfs interaction

[dholland%eecs.harvard.edu@localhost]

>Number:         40813
>Category:       bin
>Synopsis:       bad ps/ptyfs interaction
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Feb 28 22:25:00 +0000 2009
>Originator:     David A. Holland
>Release:        NetBSD 5.99.7 (20090209)
>Organization:
>Environment:
System: NetBSD tanaqui 5.99.7 NetBSD 5.99.7 (TANAQUI) #24: Mon Feb 9 11:19:51 
EST 2009 root@tanaqui:/usr/src/sys/arch/i386/compile/TANAQUI i386
Architecture: i386
Machine: i386
>Description:

With ptyfs, ps can't -t on a pseudo-tty that isn't open.

>How-To-Repeat:

Leave some processes behind on a tty (in this case from -9'ing the
wrong process after hitting the recent ptrace problem) and then try to
check for whether they've gone away or not:

tanaqui% ps xtpts/31
ps: /dev/pts/31: No such file or directory
Exit 1
tanaqui% ps aux | grep pts/31
dholland 18313  0.0  0.0    96    308 pts/30  R+    5:19PM  0:00.00 grep pts/31
dholland 17941  0.0  0.1   552   1424 pts/31- IX    5:18PM  0:00.01 -bin/tcsh -
dholland 24349  0.0  0.0     0      0 pts/31- ZW         -  0:00.00 (tcsh)
dholland 25237  0.0  0.2  2800   3676 pts/31- I     5:18PM  0:00.04 gdb trace16
tanaqui% 

>Fix:

Dunno. Why should ps need to access the pty anyway? To get its device
number?