Question: I'm using **Drupal 6.20**, **Views 2** and [**Views attach**](http://drupal.org/project/views_attach) module to append few view displays to a full node view. Is there some way to reorder the attached views? The views should still be grouped together (ie. I do not want to insert any other CCK field between them), but I want to display them in different order than that they automatically appear in.

Answer: 
If you're running on Linux, I suggest looking into eventfd - this does exactly what you're looking for.

<http://www.kernel.org/doc/man-pages/online/pages/man2/eventfd.2.html>

Open the fd in EFD\_SEMAPHORE mode and you can use it to keep track of how many queued events you have

(each write() call will increment the counter stored by the kernel with the eventfd, and each read() will decrement the counter)
If it isn't a file descriptor, then there is no point in passing it to select(). If there is a file descriptor somewhere underneath, then you either need an API to expose it, or you have a low-level API to add file descriptors to the select set and make the class responsible for registering any file descriptors it uses. Note that you are well into asynchronous event handling and callback territory then.