# File lib/new_relic/agent/pipe_channel_manager.rb, line 259
        def clean_up_pipes
          @pipes_lock.synchronize do
            @pipes.values.each do |pipe|
              if pipe.last_read.to_f + @timeout < Time.now.to_f
                pipe.close unless pipe.closed?
              end
            end
            @pipes.reject! {|id, pipe| pipe.out.closed? }
          end
        end