264:/lib/skill_raise.c (/lib/skill_raise.c)
(public int) sk_cost(int snum, int fr, int to)
/*
 * Function name: sk_cost
 * Description:   Give the cost for raising in a specific skill
 * Arguments:     snum: skill
 *                fr:   From level
 *                to:   To level
 * Returns:       Cost or 0 if it can not be tought or if fr == to.
 */
