Curtain Rod Shelf

We have an open-book case wood, with five shelves, and I want to put a curtain over it.
http://www.walmart.com/ip/Mainstays-5-Sh ...

Fortunately I have a curtain to the right height.

How can I fix it on the shelf?

I found that Home Depot sells something called a tension rod, which corresponds to 18-28 inches:
http://www.homedepot.com/h_d1/N-5yc1vZ1x ...

Can I use another?

How to use?

In fact, my shelf measures a little over 28 inches inside, so maybe I should look for a long stalk.

I want to know if there are other options cheaper hobby, like using a string or something.

Thank you!

Tension Rod was excellent and the weight of the curtain. In fact, I did it before. It requires no drilling, easily removed and does not damage the library. You'll probably need the larger rod (or buy both and return one). You just turn the rod until it fits snugly between the walls of the library and the pressure (voltage) and the rubber ends held in place. (It may fall if you pull too hard)

String sag. You can try to Velcro, but you have to secure it to the canvas. rigging is easier.

I used tension rods inside a bookshelf, it works best on a small library, because the weight of the curtain pulls down the stem if you get a piece of fabric long enough to burst I on top and put something on top, like books and book one end to hold it in place, it does not slide like a stalk, or see if a tension rod for a shower is long enough and use a the shower curtain rods for shower curtains contain many more of the small window

I like to use a coated steel wire and tie one end to not use anything that can lift the exception of your wardrobe. Another option would be a small wooden rod which may be colored corresponding to the closet.