Accessing request's raw_header from within a crontroller?

Is that something possible, i’ve been trying to get to the RAW headers
sent during a GET request on a page, and couldn’t find where. I’m using
webrick.

Here are the tries I did to get access to it:

class ZController < ApplicationController
def info
#render :inline => request.inspect
#render :inline => raw_header.inspect
#render :inline => request_line.inspect
#render :inline => req.inspect
#render :inline => meta.inspect
#render :inline => header.inspect
#render :inline => headers.inspect # --> response headers
#render :inline => $:.inspect
#render :inline => $*.inspect
#render :inline => $".inspect
#render :inline => @request.inspect
render :inline => inspect
end
end

In the scope of the controller, I can’t find such info. It seems it
could be very useful but it would somewhat be corrupting the neat
dependency on the CGI convention. I don’t care too much about this, if
it requires some tweaking of webrick or RoR, it’s ok, but I would need
to know what the simplest way.
Thanks