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iPhone Alarm Bug Leads To Mass European Sleep-in
nk497 writes "A flaw in the alarm clock in iPhone 4s gave Europeans a bit of a lie-in this morning. While the Apple handsets automatically adjusted to daylight savings time, a bug in the alarm system meant many were woken up an hour later than they should have been, after clocks rolled back over the weekend. Annoyingly, Australia was hit by a similar problem last month, but Apple failed to fix the problem or even warn users. American Apple fans, consider yourselves warned. The iOS4 bug can apparently be avoided by using one-off alarms, rather than pre-set regular wake-up calls."
Yes, its a ridiculous story.
Get a proper alarm clock for redundancy if you're in a job so sensitive that oversleeping once will get you fired, even with no history of tardiness.
If you're really paranoid, make it a wind-up clock so you don't have to worry about losing power.
The real bug is that we change the time at all, considering all the problems it brings.
With all new fancy (and not so fancy gadgets), you can NEVER be sure has the damn thing changed the time correctly or not. So you wind up watching weather forecast on TV, only to check the clock in the corner.
Note to engineers everywhere: if your gadget DO change the time, please use some kind of notification that it did so. Otherwise, we can presume that time is wrong, and that we have to manually adjust it
Not one comment yet about the real culprit here: daylight savings time. If we didn't have it anywhere in the world, then programmers wouldn't have to worry about when DST happens in different timezones (or which places have DST and which don't), or worry about what to do with log files or anything else when time jumps an hour.
Someone remind me please what we're saving? It's not electricity, because we use lightbulbs before sunrise and after sunset in summer and winter.
I don't know anybody under the age of thirty who doesn't use their phone as an alarm clock.
I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
Hi, nice to meet you, now you do.
I USED to use my phone as an alarm clock when I was in-between houses and couch-jumping from friend to friend - all of which who still live with their parents.
All in all though - I'm terrible at getting myself out of bed. Sleep is like a drug, my semi-conscious self in the mornings will battle it out mentally on whether I can spare another 5 minutes with my eyes closed or not. My phone, being a touch device, can dismiss the alarm with a simple mash, and that'll be the end of it.
Whereas my alarm clock, even with the snooze button, will continue to go off every 9 minutes at least. I've used this to my advantage though - since I know It usually takes me hitting the snooze button 5 times before getting out of bed, I just set my alarm 45 minutes early. It doesn't make a whole lot of sense, in actuallity I get less sleep this way, but it works for me.
Point is though - phones today don't cater to this rather niche area where I want to be able to look over and see what time it is whenever, and not have to pickup my phone or anything. Likewise, I want a large snooze button, and a simple way to turn it off but not so simple you can do it without some focus.
And in before someone says "Why don't you just put your alarm clock (or phone) across the room, forcing you to get out of bed before you turn it off?"
I have tried this, and it results in me falling back to sleep on the floor and not in my bed, which isn't pleasant to wake up to.
I see a lot of posts with hate for DST.. that's fine, I'd be happy if it were abolished as well.
But now back to there being a bug in how the alarm thing is handled on the iPhone. How does that bug even exist?
If the alarm is set for a particular time, say "7am".. then what does it matter whether or not the clock went back an hour at 3am? I can understand the alarm app going a bit batty if the clock went back at 8am (essentially the alarm going off -twice- that day), but given the actual circumstances... how did the alarm decide that it should instead be going off at 8am? The clock, presumably, does give the correct time.. so it's not like its internal time functions don't know what time it actually is. I'm confused. Is this just some manner of shoddy coding going on?
I'll venture a guess:
Applications, especially ones using phone APIs, usually aren't running 24/7. At a high level, what they will do is, in some manner, register for an event with the operating system. They will then idle indefinitely until that event occurs, at which point the operating system will give the application execution time and it will respond to that event. The event can be several things, including "when the user taps the screen" and "if the phone is powered on", and notably (for this discussion) can be based off of time, such as "8 hours from now".
My guess is that, when an alarm is set, the alarm calculates the amount of time in the future until it needs to be sounded, then registers with the OS to be woken that much time later (probably via some form of nanosleep iOS API derivative). If the alarm fails to factor in DST when calculating that time difference, then it'll get its event later (or earlier, or whatever) than it was expecting, and sound (and then probably calculate the next time difference and sleep until then).
On the surface, an alarm application could register for more periodic events (clock ticks, UI update loop iterations, or just sleep for seconds at a time) and evaluate if it should sound periodically. This would have easily avoided the DST issue. The problem here is that each time the event gets dispatched, the phone has to wake up to handle it, and such periodic waking would cost unnecessary battery. In fact, the OS knows how / when / for how long to sleep based on scheduler details derived from some form of these event registrations. Applications in general (and especially on battery-consuming devices) should attempt to register for the least number of events as possible, hence (I'm guessing) why they chose the time delay calculation option instead of a periodic one.
If you and your girlfriend aren't careful, you'll get Baby 1.0. That'll wake you up very early, and without fail.
No, they're as safe as houses. They use the iPhone rhythm method app for contraception so what could possibly go wron.... oh wait.
You realize there's a name for women who use the rhythm method...
Mommy
Just another day in Paradise