title: How to start emacs server only if it is not started?
body: <p>I'd like to use emacsclient to edit emails in Mutt. </p>
  
  <p>I added this in .emacs</p>
  
  <p><code>(server-start)</code></p>
  
  <p>And in .muttrc I added</p>
  
  <p><code>set editor="emacsclient -nw %s"</code></p>
  
  <p>It seems they work.
  When I start a second Emacs, it complains there is already a server running so it issues errors. How to make sure to do <code>(server-start)</code> only if the server isn't already started?</p>
  
  <p>Thanks</p>