title: Vim function hints for C
body: <p>I'm trying to achieve something simple, usually called "function hints". For example, scintilla-based editors have it:</p>
  
  <p><img src="https://i.stack.imgur.com/FrO0T.jpg" alt="enter image description here"></p>
  
  <p>You type a name, and just get the prototype. There are a few problems with that in vim:</p>
  
  <ul>
  <li>You have to rebuild the ctags to keep it up to date</li>
  <li>You can't type C-X C-O <em>after</em> the <code>(</code>, you'll just get "Pattern not found"</li>
  <li>You can't type C-X C-O in normal mode, the cursor will just jump around</li>
  <li>You get the annoying preview window at the top</li>
  </ul>
  
  <p>I've tried a few plugins; most of them mess things up even more [^1].Can anyone recommend a simple way to get just that ? A simple rectangle containing the function prototype and nothing more.</p>
  
  <p>[^1] It's really mind-numbing how idiotic some of these plugins are. One plugin (I won't mention it) actually contained <em>in the .vim file</em> a list of functions from libc.</p>