Memorize, memorize, memorize!!!
// value being pointed cannot be changed: const char * ptr;
// address of the pointer cannot be changed, // but the value being pointed can be char * const ptr;
Those rules seem to be simple, but I sometimes forgot about them ;(
// both value and the address of the pointer cannot be changed const char * const ptr;
sign image taken from: http://openclipart.org/detail/3130/warning-notification-by-eastshores