title: Variable interpolation in the shell
body: <p>I have a variable called <code>filepath=/tmp/name</code>.</p>
  
  <p>To access the variable, I know that I can do this: <code>$filepath</code></p>
  
  <p>In my shell script I attempted to do something like this (the backticks are intended)</p>
  
  <pre><code>`tail -1 $filepath_newstap.sh`
  </code></pre>
  
  <p>This line fails, duuh!, because the variable is not called <code>$filepath_newstap.sh</code></p>
  
  <p>How do I append <code>_newstap.sh</code> to the variable name?</p>
  
  <p>Please note that backticks are intended for the expression evaluation.</p>