My wife sews kids clothes and uses a curtain tension rod to hang them in a closet. She explained to me one day that the pole was frequently slipping and falling down. So, I searched and found an object that could be screwed into the wall and would fit around the ends of the tension rod: water bottle caps.
I used drywall screws to secure two water bottle caps into studs in the closet walls, and then I mounted the tension rod inside the bottle caps. The lip on each cap provides just enough support for the tension rod, so it doesn’t fall down anymore. — Rodney Sheets