hang on exit bug under Linux

[Nicolas Williams]

Markus,

This should be an FAQ on the OpenSSH site... :)

It keeps being brought up.

Nico


On Mon, Dec 10, 2001 at 09:28:35PM +0100, Markus Friedl wrote:
> On Mon, Dec 10, 2001 at 10:50:06AM -0800, Dan Kaminsky wrote:
> > Look: ssh user at host "command" needs to never, ever hang.
> 
> wrong.
> 
> it needs to hang.
> 
> it needs to hang until it can be sure that 'command' does not need
> any input.
> 
> it needs to hang until it can be sure that 'command' does not produce
> any output.
> 
> it needs to hang until 'command' exits because sshd needs to tell
> the exit status from 'command' to ssh.
> 
> 	$ ssh -n host 'exec > /dev/null 2>&1; sleep 3; exit 5' 
> 	$ echo $?
> 
> and so on.
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