title: can not use "[" symbol in awk command
body: <p>I can not use "[" symbol in awk command. Please see below</p>
  
  <pre><code>awk -F 'CDATA[|PSCRI' '{for (i=2; i&lt;=NF; i+=2) print $i}' &lt;&lt;&lt; ${y[0]}
  </code></pre>
  
  <p><strong>Throws:</strong> </p>
  
  <pre><code>awk: fatal: Unmatched [ or [^: /CDATA[|PSCRI/
  </code></pre>
  
  <p>I have also tried "\" to skip, its not working</p>
  
  <pre><code>awk -F 'CDATA\[|PSCRI' '{for (i=2; i&lt;=NF; i+=2) print $i}' &lt;&lt;&lt; ${y[0]}
  </code></pre>
  
  <p><strong>Throws:</strong> </p>
  
  <pre><code>awk: warning: escape sequence `\[' treated as plain `['
  awk: fatal: Unmatched [ or [^: /CDATA[|PSCRI/
  </code></pre>