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Thomas Ryan · 05-08-2009, 05:54 PM

The Beginning of Time -

The System Time is the number of seconds since 00:00:00 January 1, 1970 UTC (or more succinctly, the number of seconds since 1969).

http://www.go2linux.org/hwclock-linu...hardware-clock

It think it's 1969 because that is when Unix was invented - http://catb.org/esr/writings/taoup/html/ch02s01.html

I also recall that the 1969/70 times have not been changed to honor Ken and Dennis, to keep any weird SW that depends on it from breaking, are also now deliberately and obviously left "wrong" and so that a sys admin will notice and fix via the "date(1)" command. It's too easy to miss "off by one hour".

When the system reboots it resets the system time to the "Beginning of Time".

To the person who asked "Why not build in a clock?". Uh, there is a clock (time counter). What time do you suggest the system set the time to be, and when would it do that? Good luck on that one.

You can also probably think of some heuristics that help, such as "don't let time go backwards", but you won't be able to solve every case for every situation. Fly West.

So here is what happens when the time is set correctly, but a reboot happens and there is no WhisperNet (WAN off, no coverage). The system time is set back to 1970. When you next read a book, it's last page read time-stamp is saved as 1970, which means you read it a long, long time ago. The book sorts to the end of "Most Recent", and hangs out there as the last entry of your Home screen pages. Which is exactly backwards and it certainly looks like a "bug".

Ironically, if you never turn on Whispernet (or if you never have coverage), then everything will work fine. The Kindle thinks it's in 1970, but time marches forward from there and nothing is out of order. Until you reboot, oops. BTW - software updates cause at least one reboot.

The "right" answer, of course, is to let users set the time and have this manual setting override any automated setting, unless they choose otherwise. Maybe in Kindle EX 4? (Oh, and don't forget to make Daylight Savings Time work right, especially in Arizona. Settings is going to two pages for sure now, oh no...)

05-08-2009, 05:54 PM	#15
Thomas Ryan Connoisseur Posts: 62 Karma: 250 Join Date: Feb 2009 Device: Kindle	The Beginning of Time - The System Time is the number of seconds since 00:00:00 January 1, 1970 UTC (or more succinctly, the number of seconds since 1969). http://www.go2linux.org/hwclock-linu...hardware-clock It think it's 1969 because that is when Unix was invented - http://catb.org/esr/writings/taoup/html/ch02s01.html I also recall that the 1969/70 times have not been changed to honor Ken and Dennis, to keep any weird SW that depends on it from breaking, are also now deliberately and obviously left "wrong" and so that a sys admin will notice and fix via the "date(1)" command. It's too easy to miss "off by one hour". When the system reboots it resets the system time to the "Beginning of Time". To the person who asked "Why not build in a clock?". Uh, there is a clock (time counter). What time do you suggest the system set the time to be, and when would it do that? Good luck on that one. You can also probably think of some heuristics that help, such as "don't let time go backwards", but you won't be able to solve every case for every situation. Fly West. So here is what happens when the time is set correctly, but a reboot happens and there is no WhisperNet (WAN off, no coverage). The system time is set back to 1970. When you next read a book, it's last page read time-stamp is saved as 1970, which means you read it a long, long time ago. The book sorts to the end of "Most Recent", and hangs out there as the last entry of your Home screen pages. Which is exactly backwards and it certainly looks like a "bug". Ironically, if you never turn on Whispernet (or if you never have coverage), then everything will work fine. The Kindle thinks it's in 1970, but time marches forward from there and nothing is out of order. Until you reboot, oops. BTW - software updates cause at least one reboot. The "right" answer, of course, is to let users set the time and have this manual setting override any automated setting, unless they choose otherwise. Maybe in Kindle EX 4? (Oh, and don't forget to make Daylight Savings Time work right, especially in Arizona. Settings is going to two pages for sure now, oh no...) Last edited by Thomas Ryan; 05-08-2009 at 06:48 PM.