Comment 3 for bug 589715

I'm still seeing the error with the following:

$ apt-cache policy byobu
byobu:
  Installed: 2.79-0ubuntu1~ppa4
  Candidate: 2.79-0ubuntu1~ppa4

$ cat .byobu/windows
# Default windows examples
#screen -t notify-osd -M tail -f $HOME/.cache/notify-osd.log
#screen -t top top
#screen -t web elinks
#screen -t shell motd+shell
screen -t shell /bin/does_not_exist

1) Switch to tty1 (Ctrl + Alt + F1)
2) Login
3) Get a message about the inability to exec
4) Screen terminates and I am logged out.

The problem is that byobu is exiting with 0.

This can be seen if you do the following from a terminal with the
errant .byobu/windows file:

$ byobu
(Unable to exec, screen terminates)
$echo $?
0

Similarly,

$ screen does_not_exist
(unable to exec, screen terminates)
$ echo $?
0