The Sad Sack(1950)

Original title: Tire au flanc

Thanks to a bit of string-pulling by his aunt, Jean du Bois d'Ombelles, a young recruit who has blue blood in his veins, hopes to go through a nice and comfortable military service. Unfortunately he becomes Corporal Bourrache's pet aversion. Nevertheless, against all expectations, Jean ends up taking a liking for military life.