title: PHP file content echo replace by text and positioning it somewhere in HTML page
body: <p>I have a PHP script in which I control LEDs over wifi on Raspberry.</p>
  
  <pre><code>    $fileName = __DIR__.'/txt/led2.txt';
  
          if (!file_exists($fileName) || (file_get_contents($fileName) !== '1' &amp;&amp; file_get_contents($fileName) !== '0')) {
              file_put_contents($fileName, '1');
          }
  
          if (isset($_GET['on4']) &amp;&amp; file_get_contents($fileName) === '1') {
              shell_exec("/usr/local/bin/gpio -g write 15 1");
              file_put_contents($fileName, '0');
          }
  
          else if (isset($_GET['on4']) &amp;&amp; file_get_contents($fileName) === '0') {
              shell_exec("/usr/local/bin/gpio -g write 15 0");
              file_put_contents($fileName, '1');
          }
  </code></pre>
  
  <p>Basically If I press button, script will replace variable in file, when it is on, variable in file = 0 and when it is off, its equals to 1.</p>
  
  <p><strong>I need to show the current status of the LEDs on my web UI. Is it posible?
  Now I only know if the echo shows 1 or 0, could not it be replaced by some picture or text?</strong></p>