title: insert bash variable into perl search and replace
body: <p>in my bash script i look for text inside a file and replace it with a variable from my bash script.  I couldn't get the variable to be recognized by the perl command.  any ideas?</p>
  <p>mybash.bash:</p>
  <pre><code>#! /bin/sh
  let &quot;myNum=2&quot;# myNum could be any integer
  perl -pi -e 's/ABCD\d/ABCD$myNum/g' ./textfile.txt
  </code></pre>
  <p>textfile.txt:</p>
  <p>'ABCD0' gets replace with 'ABCD' with above script</p>