title: Policy in Linux file descriptor multiplexing (select et al.)
body: <p>I was wondering whether there is - at least under Linux - a system call that watches a set of file descriptors and first "serves" the first file descriptor that got ready for operation.</p>
  
  <p>I have been working with <code>select</code> and I do not expect that <code>select</code> enforces a kind of FirstComeFirstServed policy on the descriptors that watches, because its implementation should be a slight variation on polling.</p>
  
  <p>Maybe I am asking for an event-driven handler, but I do not know anything about <code>epoll</code> beyond its mere existence.</p>
  
  <p>Thanks</p>