I use this code to keep track of last reboot:
+ (float) secondsSinceLastReboot{
return ((float)(mach_absolute_time())) * ((float)timebase.numer) / ((float)timebase.denom) / 1000000000.0f;
}
I assumed mach_absolute_time() was based on last device boot time like it is on a mac. It doesn't seem to be based on that. I actually have no idea what it is based on.
Look at the following behaviour (today's date is 2009-09-20):
lastRebootTime = [[NSDate date] addTimeInterval:-[self secondsSinceLastReboot]];
//last Reboot Time will contain : 2009-09-20 07:42:14 +0100
I'm absolutely certain I did not reboot my device at that time. My device hasn't been booted in a week.
Furthermore, when I unhook my device from the cable and run this app , it seems that when the device goes to sleep, the lastRebootTime starts shifting in the future. It seems mach_absolute_time doesn't keep account for sleep time. Or am i wrong about this?
I would really like to be able to get a timestamp from when the device last rebooted. Any idea's?