Q590 How do I check for the existence of a setTimeout() and remove it?

<script language="JavaScript"><!-- 
var timerRunning = false; // boolean flag
var myTimer = null;

function myFunction() { 
    // whenever the timer 'awakes' set the flag to false: 
    timerRunning = false; 
    // insert your code here...
} 

function startTimer() {
    myTimer = setTimeout=('myFunction()',10000); // myTimer holds the id of the timer
    timerRunning = true; // whenever you start a timer set the timerRunning flag to true 
}

function stopTimer() {
    if (timerRunning)
        clearTimeout(myTimer); 
}
//--></script> 

<form>
<input type="button" value="Start" onClick="startTimer()">
<input type="button" value="Start" onClick="stopTimer()">
</form>