From: Morton Goldberg <m_goldberg@...>
Date: 2007-10-02T22:29:41+09:00
Subject: Re: Discarding putc But Not puts

On Oct 2, 2007, at 7:02 AM, Andrew Stewart wrote:

> I'm working with a third-party library that calls both putc and  
> puts in a certain method.  I'd like to discard what is written with  
> putc for the duration of the method while keeping anything written  
> to puts.  Given that the method lets you hook in your own code at  
> its start and end, how do I do this?
>
> I've tried various approaches including replacing $stdout with a  
> custom class, and opening $stdout and rewriting putc -- but I  
> haven't quite succeeded.
>
> For example, here's some code that doesn't work:
>
>   class << $stdout
>     alias :original_putc :putc
>     def putc(obj)
>     end
>   end
>
> >> putc 'b'
> => "b"   # I was hoping for no output
>
> Could anyone please show me the light?


Running the following code may cast some light on your problem.

<code>
class << $stdout
   def putc(obj)
      puts "1 called"
   end
end
class << STDOUT
   def putc(obj)
      puts "2 called"
   end
end
module Kernel
   def putc(obj)
      puts "3 called"
   end
end

putc 'b'
</code>

Regards, Morton