code: void remove(AbstractEpollChannel ch) throws IOException {
          assert inEventLoop();
  
          if (ch.isOpen()) {
              int fd = ch.socket.intValue();
              if (channels.remove(fd) != null) {
                  // Remove the epoll. This is only needed if it's still open as otherwise it will be automatically
                  // removed once the file-descriptor is closed.
                  Native.epollCtlDel(epollFd.intValue(), ch.fd().intValue());
              }
          }
      }
docs: Deregister the given epoll from this {@link EventLoop}.