Css – how to make 2 fixed-width sidebar div and 1 flexible-width main div

css

basically my html code looks like:

 <div id="leftbar"></div>
 <div id="content"></div>
 <div id="rightbar"></div>

how do i code it with css so that the all 3 divs will be side by side and leftbar and rightbar have a fixed width while content will be flexible to fill out the webbrowser.