From: Yoann Guillot <john-rubytalk@...>
Date: 2006-08-10T19:53:27+09:00
Subject: Re: net/telnet

On Thu, Aug 10, 2006 at 06:35:05PM +0900, pedro.baldanta@gmail.com wrote:
> Hi all:
> 
> I was unable to start "su -" after open telnet conexion. I got:
> 
> :-================ Timeout::Error =====================
> C:\ruby\lib\ruby\1.8/net/telnet.rb:551:in `waitfor'
>               raise TimeoutError, "timed out while waiting for more
> data"
> C:\ruby\lib\ruby\1.8/net/telnet.rb:680:in `cmd'
>             waitfor({"Prompt" => match, "Timeout" => time_out})
> C:\Documents and Settings\admin\Escritorio\telne_test.rb:12
>       localhost.cmd("su -")
> C:\ruby\lib\ruby\site_ruby\1.8/rubygems/custom_require.rb:27:in
> `require'
>         gem_original_require path
> 
> =============================================
> Exception: timed out while waiting for more data
> 
> 
> Any idea?
> 
> 

Telnet uses a regex to match the shell prompt, so that it knows that the
preceding command has terminated.
When you 'su -', you change the prompt (probably a $ becomes a #, or
your login changes), so Telnet never sees the end of the 'su -' command.
You should change the regex used to match the prompt when you create the
Net::Telnet object, so that it matches both your normal prompt and the
root prompt, i.e

conn = Net::Telnet.new('Host' => 'bla', 'Prompt' => /me@host\$|root@host#/)

Yoann