hang on exit - bug or no bug?

[mouring at etoh.eviladmin.org]

On Fri, 5 Oct 2001, Markus Friedl wrote:

> On Fri, Oct 05, 2001 at 11:06:01AM -0400, Nicolas Williams wrote:
> > I can certainly confirm, from experience, that, on Solaris,
> >
> > rsh host command&
> >
> > hangs if "command" keeps its stdio open. Rlogin is what others are
> > saying doesn't do this, but, so what?
> >
> > As Lee Eakin explained yesterday, there's things SSH does that RLOGIN
> > doesn't, such as agent forwarding, X forwarding, port forwarding, all
> > of which may or may not be needed by that background command that's
> > still holding its stdio open.
>
> the hang-on-exit problem is not related to forwarding.
>
> > Perhaps there should be an option, that causes SSHD to exit when its
> > child exits and the session was a TTY session, and to hell with grand-
> > children's stdio. But the conservative behaviour needs to be available
> > too.
>
> perhaps it's acceptable to discard data for sessions with ttys,
> but i'm not sure yet.
>
> session.c:session_exit_message()
>
>         if (c->ostate != CHAN_OUTPUT_CLOSED)
> 		chan_write_failed(c);
> +	if (s->ttyfd != -1 && option.discard && c->istate == CHAN_INPUT_OPEN)
> +		chan_read_failed(c);
>         s->chanid = -1;
>
> should help.
>

I assume this is part of a bigger patch  where 'option.discard' exists.

One may suggestion only activing this code for slogin only.  That way it
would mirror rsh/rlogin.

- Ben