title: What does '|' mean in file /proc/sys/kernel/core_pattern?
body: <pre><code>$ cat /proc/sys/kernel/core_pattern
  |/usr/share/apport/apport %p %s %c %d %P
  </code></pre>
  
  <p>What does '|' mean in file <code>/proc/sys/kernel/core_pattern</code>?</p>