title: UNIX sort ignores whitespaces
body: <p>Given a file <code>txt</code>:</p>
  
  <pre><code>ab
  a c
  a a
  </code></pre>
  
  <p>When calling <code>sort txt</code>, I obtain:</p>
  
  <pre><code>a a
  ab
  a c
  </code></pre>
  
  <p>In other words, it is not proper sorting, it kind of deletes/ignores the whitespaces! I expected this to be the behavior of <code>sort -i</code> but it happens with or without the <code>-i</code> flag.</p>
  
  <p>I would like to obtain "correct" sorting:</p>
  
  <pre><code>a a
  a c
  ab
  </code></pre>
  
  <p>How should I do that?</p>