We study the specific heat of the x−y model on lattices L×L×H with L≫H (i.e. on lattices representing a film geometry) using the
Cluster Monte--Carlo method. In the H--direction we apply Dirichlet boundary
conditions so that the order parameter in the top and bottom layers is zero. We
find that our results for the specific heat of various thickness size H
collapse on the same universal scaling function. The extracted scaling function
of the specific heat is in good agreement with the experimentally determined
universal scaling function using no free parameters.Comment: 4 pages, uuencoded compressed PostScrip