I remember coming home and turning on the tv and the thing I remember from the movie was someone is in a projection room and either trips or the film starts to unreel and covers the person. The person then gets up and is covered in the film strip. It might have been the ending, and it might be a short film.
I saw this around 1984 maybe 1985 and the movie might be older. Would have been on hbo and I had just arrived from school when I saw this.