I don't recommend the use of EF-s lenses on EOS film cameras, that said they can be used, with certain caveats...
N.B. most of this is based on the Canon EF-s 10-22, other lens details may vary
EF-s lenses are designed to protrude further into the camera body, however on certain lenses the protrusion is relative to zoom length. Thus you can get away with certain (longer) focal lengths. You can take off the rear cap and watch how the lens moves to give you an idea of this.
EF-s lenses have a plastic rear baffle that physically prevents their mounting on 35mm bodies, however this can (in the case of the 10-22) be removed and replaced.
Vignetting will likely occur. Again this is focal length dependant, longer is usually better. Some lenses such as the 17-55 f/2.8 are known to vignette badly at all focal lengths.
Finally it is commonly stated that using an EF-s lens on a 35mm body will break the lens and camera. This vastly overestimates the amount of force used to move the mirror! I know from experience that the mirror can hit the back of the lens and damage neither.