フリー問題

問題文

A cache is set up for the descriptors of the logs whose names carry variables. How does the documentation say that cache behaves?

選択肢

1. It shuts the descriptor that was opened least recently once the cache has filled up, and it holds a descriptor open where the uses inside the idle window reach the floor.
2. It shuts the descriptor that was opened least recently once the cache has filled up, and it holds a descriptor open where the bytes inside the idle window reach the floor.
3. It shuts the descriptor that was used least recently once the cache has filled up, and it holds a descriptor open where the bytes inside the idle window reach the floor.
4. It shuts the descriptor that was used least recently once the cache has filled up, and it holds a descriptor open where the uses inside the idle window reach the floor.