title: Total number of lines in a directory
body: <p>I have a directory with thousands of files (100K for now). When I use <code>wc -l ./*</code>, I'll get: <br></p>
  
  <pre><code> c1            ./test1.txt
   c2            ./test2.txt
   ...
   cn            ./testn.txt
   c1+c2+...+cn  total
  </code></pre>
  
  <p>Because there are a lot of files in the directory, I just want to see the total count and not the details. Is there any way to do so?</p>
  
  <p>I tried several ways and I got following error:<br>
  <code>Argument list too long</code></p>