code: func (p *PTYReqParams) Check() error {
  	if p.W > maxSize || p.W < minSize {
  		return trace.BadParameter("bad width: %v", p.W)
  	}
  	if p.H > maxSize || p.H < minSize {
  		return trace.BadParameter("bad height: %v", p.H)
  	}
  
  	return nil
  }
docs: // Check validates PTY parameters.