}

// RawRead invokes the user-defined function f for a read operation.
func (fd *FD) RawRead(f func(uintptr) bool) error {
	return errors.New("not implemented")
}

// RawWrite invokes the user-defined function f for a write operation.
func (fd *FD) RawWrite(f func(uintptr) bool) error {
	return errors.New("not implemented")
}

func DupCloseOnExec(fd int) (int, string, error) {
	nfd, err := syscall.Dup(int(fd), -1)