def send_stdin(io = nil)
      unless io.nil?
        begin
          send_chunk :stdin, io.read(2048)
        end until io.eof?
        io.close
      end
      send_chunk :stdin_eof
    end
def send_stdin(io = nil)
      unless io.nil?
        begin
          send_chunk :stdin, io.read(2048)
        end until io.eof?
        io.close
      end
      send_chunk :stdin_eof
    end
Private: Send the STDIN stream for the Nail to read from.

 io = nil - an IO of the stdin stream to send.