title: Sed not working inside bash script
body: <p>I believe this may be a simple question, but I've looked everywhere and tried some workarounds, but I still haven't solved the problem.</p>
  
  <p>Problem description:
  I have to replace a character inside a file and I can do it easily using the command line:</p>
  
  <pre><code>sed -e 's/pattern1/pattern2/g' full_path_to_file/file
  </code></pre>
  
  <p>But when I use the same line inside a bash script I can't seem to be able to replace it, and I don't get an error message, just the file contents without the substitution.</p>
  
  <pre><code>#!/bin/sh
  
  VAR1="patter1"
  VAR2="patter2"
  
  VAR3="full_path_to_file"
  
  sed -e 's/${VAR1}/${VAR2}/g' ${VAR3}
  </code></pre>
  
  <p>Any help would be appreciated.</p>
  
  <p>Thank you very much for your time.</p>