title: How to clear a QSharedMemory
body: <p>I have an application which continuously polls a <code>QSharedMemory</code> to check if something's been written into it.</p>
  
  <p>But once something has been written and retrieved, I'd like to clear the shared memory of its content. </p>
  
  <p>Is there a way to do it? I do not wish to detach and attach to it again, as I might wish vital information.</p>