title: Create or reuse existing Emacs GUI frame
body: <p>Assuming an Emacs server is running, I want <code>emacsclient &lt;file&gt;</code> to either create a new frame (like <code>-c</code>) when there is no existing frame or reuse an existing frame when there is one. In other words, I want the <code>-c</code> only when there is no existing frame. Is that possible?</p>