title: invoking swi-prolog from php
body: <p>I am trying to invoke swi-prolog from within a php script like :</p>
  
  <pre><code>exec("start plwin.exe -f C:\\path\\load.pl -g run_from_file.", $os1);
  print_r($os1);
  </code></pre>
  
  <p>I can see that prolog window gets opened and complies the file, but immediately exits displaying an exit status as 1. I am sure that it is not executing the predicate I want to to execute. </p>
  
  <p>Is there any other to invoke prolog with appropriate parameters and keep the window <code>open</code> without automatically exiting?</p>
  
  <p>UPDATE : I configured the system env variables to the path where prolog is installed.</p>