Ending a javascript function

Ending a javascript function

I have an html page that links to a js file that has the following function:
function show360Simple( divContainerId, imageUrl )
The function gets called on an on-click:
<area onclick="show360Simple('pContainer5','images/porch1.jpg');">
And I want to know how to end the function with another on-click:
<div id="close-div" onclick="what is the syntax here to end the above
function?"></div>
Its probably simple but I'm a novice and haven't been able to work it out
yet - any help is greatly appreciated - cheers.