5 Replies
      Latest reply on May 3, 2018 2:09 PM by Bjvb09
      Bjvb09 Level 1 Level 1 (0 points)

        Hello! I have a question. Is there a way to get the last time that the phone was booted?  I found this:




        But it give me the time since the last time the phone was turned off, and I need to know the time since the last time the phone was switched on. I don't know if this is possible.

        • Re: System Uptime
          Claude31 Level 8 Level 8 (7,825 points)

          That's a bit surprising, as doc states :


          var systemUptime: TimeInterval

          The amount of time the system has been awake since the last time it was restarted.

          • Re: System Uptime
            eskimo Apple Staff Apple Staff (12,675 points)

            systemUptime is not the droid you’re looking for.  However, the problem is not what you think it is.  You wrote:

            But it give me the time since the last time the phone was turned off …

            which is incorrect.  Rather, the problem is sleep.  systemUptime only counts time while the system has been awake, and our devices sleep a lot.

            You can get the boot time (that is, the clock time when the system booted) using the kern.boottime sysctl.  Here’s a snippet:

            func bootTime() -> Date? {
                var tv = timeval()
                var tvSize = MemoryLayout<timeval>.size
                let err = sysctlbyname("kern.boottime", &tv, &tvSize, nil, 0);
                guard err == 0, tvSize == MemoryLayout<timeval>.size else {
                    return nil
                return Date(timeIntervalSince1970: Double(tv.tv_sec) + Double(tv.tv_usec) / 1_000_000.0)

            Be aware that this time will change if the system clock changes, that is, the value is the boot time relative to the current system clock.

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