code: func (e *Epoller) CloseConsole(fd int) error {
  	e.mu.Lock()
  	defer e.mu.Unlock()
  	delete(e.fdMapping, fd)
  	return unix.EpollCtl(e.efd, unix.EPOLL_CTL_DEL, fd, &unix.EpollEvent{})
  }
docs: // CloseConsole unregisters the console's file descriptor from epoll interface