In a 6-quart kettle bring 5 quarts salted water to a boil for linguine. In a 12-inch heavy skillet cook garlic in 3 tablespoons oil over moderate heat, stirring, until pale golden and transfer with a slotted spoon to a small bowl. To skillet add red pepper flakes, wine, and salt and boil until reduced to about 1/4 cup. Keep wine mixture warm. Boil linguine until al dente. Reserve 11/2 cups pasta water and drain linguine. Stir 1 cup reserved pasta water and parsley into wine mixture and add linguine, garlic, and remaining tablespoon oil. Toss pasta over moderate heat until combined well, about 1 minute, adding more pasta water if necessary to keep mixture moist. Serve pasta with Parmesan.
