[maemo-developers] sensing change in System Clock using Qt

[From: Remi.Denis-Courmont at nokia.com]

   Hello,

----- Message d'origine -----
> But the problem that can face me is the case when the user changes his
> clock settings (i.e adjust phone's time to a different time). in this
> case, the timer that has been set to some fixed duration can go wrong.

As a general rule, delay measurements should be done with the monotonic clock, not the wall clock (the real-time clock). As far as I know, Qt timers already do so internally. But of course, your own code should never request and use the wall clock for time measurements.

> One solution i figured is to check for system time change every fixed
> period (say a minute). But it seems a very ugly one since it is bad for
> performance and not handy (wait for the next minute to come to check
> for
> the clock and realize it was changed)

This is awful and pointless.

> my question is: is there any way to get notified by the system clock of
> any change/adjustments ? any signals sent by the system phone or
> something like that ?

That is not something you should be concerned with in the first place. If you do, it is a very strong hint that you are using the wrong clock.