I could not find this movie on the Google: actually it has been seen by my family, but not by me, and the Serbian translation of the title was "The Shipwrecker". The film is probably English or American.
It is about the shipwrecker, who escaped from his boat on the float, with some drinking water, diary, and obviously some kind of pen. During the floating, he was able to write about his adventures. Eventually, he saw a ship, but decided not to be saved: allegedly, he wrote something like: "I saw His face, so I should not return among those who live". Only his float and diary were eventually found.
Allegedly, this film also won some prizes a couple of years ago.