title: Escaping slash "\" in grep
body: <p>I have file with line: </p>
  
  <pre><code>"H:\Check\WP_20140511_029.mp4"
  </code></pre>
  
  <p>along with other lines. I want to remove such lines indicating directory at <code>H:\Check</code>. I tried</p>
  
  <pre><code>grep -v ".*H:\\Check.*" testout.txt &gt; testout2.txt
  </code></pre>
  
  <p>But it did not delete those lines. Whats wrong with my regex <code>.*H:\\Check.*</code>.
  <a href="https://regex101.com/r/7I65QQ/1/" rel="nofollow noreferrer">regex101 shows</a> that my regex correctly matches the line.</p>