a lock before a read or write. See, it’s a kind of <em>cooperative</em> locking system. This is easily sufficient for almost all cases where file locking is necessary.</p>
<p>Since that’s out of the way, whenever I refer to a lock from now on in this document, I’m referring to advisory locks. So there.</p>
<p>Now, let me break down the concept of a lock a little bit more. There are two types of (advisory!) locks: read locks and write locks (also referred to as shared locks and exclusive locks, respect