Nicolas.Williams at Nicolas.Williams at
Tue Aug 6 06:31:26 EST 2002

Fair enough on the flushing of the pty. But sshd should still
not close the pty - it should wait for the background processes
to exit and/or dissassociate from the pty.

The client does know that there are background processes left
still holding the pty open. How? Because the client requested
and got a pty, the sshd has sent a session-exit message, and
the channel is still open.



> -----Original Message-----
> From: Jani Jaakkola [mailto:jjaakkol at cs.Helsinki.FI]
> Sent: Monday, August 05, 2002 4:20 PM
> To: Williams, Nicolas
> Cc: openssh-unix-dev at
> Subject: RE: so-called-hang-on-exit
> On Mon, 5 Aug 2002 Nicolas.Williams at wrote:
> > 
> > I still think this sort of thing should be done by the client.
> > 
> > The client knows everything that the server knows.
> Except this time is does not. If there is background 
> processses on the 
> tty, the client can either close the session and lose data or wait 
> indefinetely for data from the background processes.
> > So the client
> > can choose to terminate the SSHv2 session when the PTY session
> > process leader exits - and it can implement any other termination
> > heuristic you wish too.
> It needs server modifications that data from the pty session process 
> leaders is not lost. I think rlogin and all other pty using 
> programs have 
> allready implemented this properly; which is that the pty buffer is 
> first emptied and the connection is closed _after_ that.
> - Jani

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