Top 5 replys modification

[Martz]

The following code is from a hack which lists the last 5 threads which have been posted too. However I have provate forums, and they show up in this list as well. How can I modify this:

PHP Code:

// Top 5 Thread Replys
$pop = $DB_site->query('SELECT title,threadid,lastpost,lastposter,views FROM thread ORDER BY lastpost DESC LIMIT 5');
while ($poptop = mysql_fetch_array($pop)):
    ++$poptopnbsp;
    $popthread .= "<a href=showthread.php?s=$session[sessionhash]&threadid=$poptop[threadid]>$poptop[title]</a><br>";
    $poplastposter .= "$poptop[lastposter]<br>";
    $popviews .= "$poptop[views]<br>"; 


So that it only shows threads from forums the user can actually see?

Could I use something like:

PHP Code:

$perms=getpermissions();
  if (!$perms[ismoderator].... 


but using ($perms[canviewforum]) or something similar?

sorry im a newbie, but I'm willing to give any advice a shot.