# File lib/net/ssh/connection/session.rb, line 168
    def process(wait=nil, &block)
      return false unless preprocess(&block)

      r = listeners.keys
      w = r.select { |w| w.respond_to?(:pending_write?) && w.pending_write? }
      readers, writers, = IO.select(r, w, nil, wait)

      postprocess(readers, writers)
    end