/**
  * set block position
  *
  * @access public
  * @param int $bid block id
  * @param bool $visible visible flag
  * @param int $side
  *        0: sideblock - left
  *        1: sideblock - right
  *        2: sideblock - left and right
  *        3: centerblock - left
  *        4: centerblock - right
  *        5: centerblock - center
  *        6: centerblock - left, right, center
  * @param int $weight weight
  * @return bool false if failure
  */
 function setBlockPosition($bid, $visible, $side, $weight)
 {
     $block = new XoopsBlock();
     $block->load($bid);
     if (!is_null($visible)) {
         $block->setVar('visible', $visible ? 1 : 0, true);
         // not gpc
     }
     if (!is_null($side)) {
         $block->setVar('side', $side, true);
         // not gpc
     }
     if (!is_null($weight)) {
         $block->setVar('weight', $weight, true);
         // not gpc
     }
     return $block->store();
 }