What happens to setTimeout when the computer goes to sleep?

In a modern web browser, suppose I do a setTimeout for 10 minutes (at 12:00), and 5 minutes later put the computer to sleep, what should happen when the system wakes up again? What happens if it wakes up before the 10 minutes are up (at 12:09) or much later (at 16:00)?

The reason I'm asking is because I'd like to have a new authentication token requested every 10 minutes, and I'm not sure if the browser will do the right thing and immediately request a new token if it wakes up after a long time.

Clarifications: I don't wan't to use cookies - I'm trying to build a web service here; and yes, the server will reject old and invalid tokens.

As far as I've tested, it just stops and resumes after the computer wakes up. When the computer awakes the setInterval/setTimeout is unaware that any time passed.

I don't think you should rely on the accuracy of setTimeout/Interval for time critical stuff. For google chrome I discovered recently that any timeout/interval (that is shorter than 1s) will be slowed down to once a second if the tab where it's activated looses focus.

Apart from that the accuracy of timeouts/intervals is dependent on other functions running etc. In short: it's not very accurate.

So using interval and timeouts, checking the time against a starttime within the function started by it would give you better accuracy. Now if you start at 12:00, the computer goes to sleep and wakes up at 16:13 or so, checking 16:13 against 12:00 you are certain you have to renew the token. An example of using time comparison can be found here

Compare current datetime against datetime when the page was loaded, like so:

//Force refresh after x minutes.
var initialTime = new Date();
var checkSessionTimeout = function () {
    var minutes = Math.abs((initialTime - new Date()) / 1000 / 60);
    if (minutes > 20) {
        setInterval(function () { location.href = 'Audit.aspx' }, 5000)
    } 
};
setInterval(checkSessionTimeout, 1000);

Here is my code :

<!doctype html>
<html>

<body>
<input type="button" name="clickMe" id="colourButton" value="Start Timer" onclick="setTimeout('alert(\'Surprise!\')', 120000)"/>

</body>
<script>


</script>
</html>

I have taken three scenarios that might answer the question.

Scenario 1: At 00 Seconds click on 'Start Timer' button . At 25 seconds computer falls asleep. At 1min 40 seconds wake up computer. At 2mins Alert is displayed.

Scenario 2 : At 00 Seconds click on 'Start Timer' button . At 26 seconds computer falls asleep. At 3 mins, I wakeup the computer. The Alert is displayed.

Scenario 3 : This one is truly astounding.

<input type="button" name="clickMe" id="colourButton" value="Start Timer" onclick="setTimeout('alert(\'Surprise!\')', 600000)"/>

At 00 Seconds I click on 'Start Timer' button. At around 1min 30 seconds the computer is on hibernate mode (my pc takes a minute to initiate hibernate)

At 8 mins I turn the laptop on. At 10 mins exactly, the alert pops up.

PS: This is my first ever comment on Stack Exchange. I prefer to execute code and view results rather than infer from theory.

What happens to setTimeout when the computer goes to sleep?

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