How to implement push button bar in Cocoa

Any idea how to recreate the row of buttons effect used by Safari 5.1 for the back/next buttons, or in Xcode 4 for the Editor and View buttons in the toolbar? Basically a set of buttons in a single block, with a thin separator line between each, and rounded corners at the ends.

I don't see anything in the standard controls, but perhaps I just don't know what to search 开发者_StackOverflowfor. Thanks!

Update: here's an image to show what I mean:

Have a look at NSSegmentedControl in interface builder library, try playing with its style attribute.. I hope you will be able to get what you are looking for !