title: flock vs lockf on Linux
body: <p>If <code>lockf</code> is used with a 0 offset, what are differences between <code>flock</code> and <code>lockf</code> when used in exclusive mode, if any?</p>
  
  <p>I'm asking because I'm reading code that conditionally compiles in either of these 2 functions based on platform and I want to understand possible reasons why.</p>