487:/lib/skill_raise.c (/lib/skill_raise.c)
(int) sk_hook_improve_unknown(string skill)
/*
 * Function name: sk_hook_improve_unknown
 * Description  : Player wants to improve a skill he has never learned.
 * Arguments    : string skill - the skill the player tried to improve.
 * Returns      : int 0 - as always with notify_fail.
 */
