title: Return multiple results using xmllint
body: <p>I am trying to extract all sections of an XML file which contain a specified tag. I have search the web and found this which works.</p>
  
  <pre><code>xmllint --xpath "/all/string(//title)"
  </code></pre>
  
  <p>But it only returns the first result, how can I make it find all results? Thanks!</p>
  
  <p>Sample XML</p>
  
  <pre><code>&lt;programme start="20170913125500 +0100" stop="20170913144500 +0100" channel="3b6963d34ba31ea21db5c3aee8e3b26f"&gt;
    &lt;title lang="eng"&gt;Yangtse Incident&lt;/title&gt;
    &lt;sub-title lang="eng"&gt;(1957) Michael Anderson&amp;apos;s drama, starring Richard Todd and William Hartnell, tells the true story of HMS Amethyst, a British frigate captured by Chinese communists during Mao&amp;apos;s revolution.  [AD,S]&lt;/sub-title&gt;
  &lt;/programme&gt;
  &lt;programme start="20170913144500 +0100" stop="20170913165500 +0100" channel="3b6963d34ba31ea21db5c3aee8e3b26f"&gt;
    &lt;title lang="eng"&gt;The Comancheros&lt;/title&gt;
    &lt;sub-title lang="eng"&gt;(1961) Western starring John Wayne and Stuart Whitman. A Texas Ranger is forced to team up with his prisoner while he&amp;apos;s on a covert mission to take on a band of thieves and gunrunners.  [S]&lt;/sub-title&gt;
  &lt;/programme&gt;
  &lt;programme start="20170913165500 +0100" stop="20170913185500 +0100" channel="3b6963d34ba31ea21db5c3aee8e3b26f"&gt;
    &lt;title lang="eng"&gt;The Cockleshell Heroes&lt;/title&gt;
    &lt;sub-title lang="eng"&gt;(1955) World War II drama. In a true-life tale of incredible bravery, ten marines try to break the blockade of Bordeaux. With José Ferrer, Trevor Howard, Victor Maddern and Anthony Newley.  [S]&lt;/sub-title&gt;
  &lt;/programme&gt;
  &lt;programme start="20170913185500 +0100" stop="20170913190500 +0100" channel="3b6963d34ba31ea21db5c3aee8e3b26f"&gt;
    &lt;title lang="eng"&gt;Dunkirk Interview Special&lt;/title&gt;
    &lt;sub-title lang="eng"&gt;Stars Harry Styles, Mark Rylance, Jack Lowden, Fionn Whitehead and Tom Glynn-Carney talk about making director Christopher Nolan&amp;apos;s intense Second World War dramatic thriller.  [S]&lt;/sub-title&gt;
  &lt;/programme&gt;
  </code></pre>
  
  <p>Result should be</p>
  
  <pre><code>Yangtse Incident
  The Comancheros
  The Cockleshell Heroes
  Dunkirk Interview Special
  </code></pre>