code: func (i *In) SetRawTerminal() (err error) {
  	if os.Getenv("NORAW") != "" || !i.commonStream.isTerminal {
  		return nil
  	}
  	i.commonStream.state, err = term.SetRawTerminal(i.commonStream.fd)
  	return err
  }
docs: // SetRawTerminal sets raw mode on the input terminal