title: use rename command on first 5 characters of a file
body: <p>using linux's rename utility
  I have files that are named similar to</p>
  
  <pre><code>kbb.12.06.14.actual_name.jpg
  kbb.13.05.13.actual_name.jpg
  kbb.11.11.29.actual_name.jpg
  </code></pre>
  
  <p>and I want to change that to </p>
  
  <pre><code>actual_name.kbb.12.06.14.jpg
  actual_name.kbb.13.05.13.jpg
  actual_name.kbb.11.11.29.jpg
  </code></pre>
  
  <p>I know I can get the beginning of a file with</p>
  
  <pre><code>rename 's/^/something/' *
  </code></pre>
  
  <p>but is there a way to select from the beginning to a certain length in the file? Similar to an array.</p>