title: mkdir -p returns error " file exists"
body: <p>I tried <code>mkdir -p /a/b/c</code> on AIX. When <code>a</code> and <code>b</code> didn't exist, this command created <code>a</code>, <code>b</code> and <code>c</code>. But when <code>a</code> and <code>b</code> both exists, it gives an error </p>
  
  <blockquote>
    <p>Cannot create /a/b. /a/b: File exists</p>
  </blockquote>
  
  <p>and returns an error code 2.</p>
  
  <p>Any help on this?</p>