code: public function set(string $sName, $mValue, int $iFlag = 0, int $iExpire = false)
      {
          return true;
      }
docs: set a value
  
  @access public
  @param  string $sName name of the session
  @param  mixed $mValue value of this sesion var
  @param  int $iFlag unused
  @param  int $iExpire expiration of cache
  @return boolean