From: "Ara.T.Howard" <ahoward@...>
Date: 2004-04-15T01:09:20+09:00
Subject: Re: ruby pty/expect help

On Wed, 14 Apr 2004, ts wrote:

> >>>>> "A" == Ara T Howard <Ara.T.Howard@noaa.gov> writes:
> 
> A> i've been up for a really long time, so perhaps i'm missing something silly,
> A> but this script 'seems' to work (all three dots are printed), but no id_rsa
> A> file is made? 
> 
>  You must read its output

thanks guy - what exactly do you mean?  there's only one thing to read, and
reading it seems the throw errors:

~/eg/ruby > cat ssh-keygen.rb 
require 'pty'
require 'expect'
$VERBOSE=nil

path = ARGV.shift || 'id_rsa'
File.unlink path rescue nil

PTY.spawn 'ssh-keygen -t rsa' do |r,w,cid|
  r.expect %r/^Enter.*:\s+/ do |line|
    print line
    w.puts path 
  end
  r.expect %r/^Enter.*:\s+/ do |line|
    print line
    w.puts ''
  end
  r.expect %r/^Enter.*:\s+/ do |line|
    print line
    w.puts ''
  end

  r.read  # ?? this raises Errno::EIO 
  w.flush
  w.close
  puts
end


~/eg/ruby > ruby ssh-keygen.rb 
Generating public/private rsa key pair.
Enter file in which to save the key (/home/ahoward/.ssh/id_rsa): id_rsa
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: ssh-keygen.rb:22:in `read': Input/output error - /dev/pts/19 (Errno::EIO)
        from ssh-keygen.rb:22
        from ssh-keygen.rb:8:in `spawn'
        from ssh-keygen.rb:8


without the read it generates the expected output, but no id_rsa file is
produced and no error is given...  doesn't the call to IO.expect do the reading
anyhow?  also, the example in ext/pty/example_expect.rb doesn't seem to do any
reading either?

> A> do i have to signal the child to die or something?  any other
> A> useful debugging tips? 
> 
>    $expect_verbose = true
> 
> 
> Guy Decoux

this is very helpful - and it was right in the example! ;-)


-a
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