kern/39066: tty settings messed up

[christos%zoulas.com@localhost]

>Number:         39066
>Category:       kern
>Synopsis:       Tty settings mangled.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Jun 29 16:55:00 +0000 2008
>Originator:     Christos Zoulas
>Release:        NetBSD 4.99.64
>Organization:
        Entropy, Inc.
>Environment:
NetBSD shiny.astron.com 4.99.64 NetBSD 4.99.64 (SHINY) #160: Sun Jun  1 
18:01:37 EDT 2008  
christos%shiny.astron.com@localhost:/usr/src/sys/arch/i386/compile/SHINY i386
Architecture: i386
Machine: i386
>Description:
        Wrong process sets tty settings, or tty process group is messed up?

>How-To-Repeat:
0) mail foo
1) from the mail editor, start "~! emacs -nw" (21.4)
2) suspend emacs to the shell (bash 3.2.25)
3) resume emacs
4) exit emacs back to the mail editor
5) discover the tty is screwed: the mail editor is no
   longer receiving characters

- This occurs on both i386 and amd64.
- This did _NOT_ occur before 4.99.10.
- This does _NOT_ occur if the editor is vi(1) or if the shell
  is /bin/sh.
- This is the commit that introduced this "feature":
- http://mail-index.netbsd.org/source-changes/2007/02/09/0020.html

>Fix:

Unknown