Do you get skill points retroactively for increased Int?

In D&D 3.5 you don’t get skill points retroactively, only from the next level onwards after you increase your intelligence enough to gain an increased bonus, leading to extra skill points per level.

However when playing today a friend of mine mentioned that Pathfinder is different, and that skill points are applied retroactively when your intelligence bonus increases. But I can’t find anything in the rule book that mentions which it is either way.

Can someone please clarify for me which it is and point out where it is stated?