title: PHP shell_exec() doesn't allow less-than "<" character or "<()" command to be used?
body: <p>I need to run this exact shell command from PHP shell_exec():</p>
  <pre><code>/usr/bin/paste -d'|' &lt;(echo $(id)) &lt;(echo $(pwd))
  </code></pre>
  <p>From a VPS shell (Debian) it works perfectly. However, from shell_exec() it doesn't work:</p>
  <pre><code>$command = &quot;/usr/bin/paste -d'|' &lt;(echo $(id)) &lt;(echo $(pwd)) 2&gt;&amp;1&quot;;
  
  $output = shell_exec($command);
  
  print_r($output);
  </code></pre>
  <p>It doesn't output anything, the output is just blank/empty.</p>
  <p>I am using PHP 7.3 with safe_mode = On and open_basedir, shell_exec() is enabled.</p>
  <p>How can I run that command with shell_exec()?</p>
  <p>I think the less-than &quot;&lt;&quot; char or &quot;&lt;()&quot; create problems?</p>