How do I implement a circular list (ring buffer) in C?

Question

How do I implement a circular list that overwrites the oldest entry when it\'s full?

For a little background, I want to use a circular list within GWT; so using a 3

Answer 1

Use an array and keep a variable P with the first available position.

Increase P every time you add a new element.

To know the equivalent index of P in your array do (P % n) where n is the size of your array.