code: func (s *Session) StdoutPipe() (io.Reader, error) {
  	if s.Stdout != nil {
  		return nil, errors.New("ssh: Stdout already set")
  	}
  	if s.started {
  		return nil, errors.New("ssh: StdoutPipe after process started")
  	}
  	s.stdoutpipe = true
  	return s.ch, nil
  }
docs: // StdoutPipe returns a pipe that will be connected to the
  // remote command's standard output when the command starts.
  // There is a fixed amount of buffering that is shared between
  // stdout and stderr streams. If the StdoutPipe reader is
  // not serviced fast enough it may eventually cause the
  // remote command to block.