Are you looking for something like shown below, where the slot can be cut into one surface (facet) of the cylinder?
If so, here is a solution;
1. select opposit surfaces, "Make a Hole"
2. Select all four verts of both holes (8 verts total)
3. "Create Convex Surface/Object"
4. Select and delete slot openning surfaces
5. if you want, "merge" the objects (the hole liner and the post) into one
More complex requirements (e.g., cross slots) would require a slightly more complex solution.
Or - if you are just trying to create the "illusion" of a slot for something like a rail, just create the rail to pass through the post, as in the last example, but then this is not what you asked for -
The AC3D (.ac) file for this can be obtained at:
http://www.mr-fab.com/gallery/AC3D/Examples/Post01.ac
Other people on the forum may have other ideas.
Good luck with your project!
Eldon
and
The illusion:
