I found the archive. 
(http://blade.nagaokaut.ac.jp/ruby/comp.lang.ruby/index.shtml#comp.lang.ruby)

> Hi,
>
> I'm putting out some text in a window using a TkLabel. The problem is
> that the text only seems to appear once the method has finished.
> Is there a way to make labels update after .configure immediately?
>
> Code example:
>   btnExit = TkButton.new() do
>     text "Exit"
>     command {
>       label.configure ("text" => 'Good bye!') #never appears!
>       sleep 2
>       exit
>     }
>   end
>
> Thanks!
> Ralf.
>
> pm. Is there an "official" tk and/or gtk newsgroup? Where can I find the
> archive of this Ruby group?
>