title: awk to update existing file
body: <p>As a follow up to this question - <a href="https://stackoverflow.com/questions/56636453/grep-and-awk-combine-commands">grep and awk, combine commands?</a></p>
  
  <p>Using a command such as </p>
  
  <pre><code>awk '/^-/{ print $9 }' file &gt; outputfile
  </code></pre>
  
  <p>How can I awk a file and have the output redirected to the same file name?</p>
  
  <p>I tried</p>
  
  <pre><code>awk '/^-/ {print $9}' outfile.log &gt;outfile.log
  </code></pre>
  
  <p>..but the resulting outfile.log comes up empty.</p>