hang on exit bug under Linux

[mouring at etoh.eviladmin.org]

On Mon, 10 Dec 2001, Nicolas Williams wrote:

>  - with no ptys, you want to make sure that your remote command closes
>    all its stdio and you get no hang (there was a hang bug wrt
>    agent/x11/port forwarding).
>
>  - with pty you may want sshd to do killpg() on the pty/tty process
>    groups when the client closes the session.
>
Markus suggsted this and threw together a small patch, but I've
been able to test it since my test servers are still scattered all
over Minnesota and I'm only slowly now reclaiming them and putting them
into my house.

- Ben