code: func Select(n int, r, w, e *FDSet, timeout time.Duration) error {
  	var timeval *syscall.Timeval
  	if timeout >= 0 {
  		t := syscall.NsecToTimeval(timeout.Nanoseconds())
  		timeval = &t
  	}
  
  	return sysSelect(n, r, w, e, timeval)
  }
docs: // Select wraps syscall.Select with Go types