Source of 'timestamp' Data in "Device" 'Date' Column

otta56 · 05-05-2020, 04:23 PM

Hello,

Using Calibre version 4.15 to export book files and metadata to 'device' always results in the device date column showing '31 Dec 1970'. Calibre always shows the time the book was first loaded into the calibre library.

The clock time on the device and computer are correct and synchronized with NTP.

So the question I have is where is the timestamp data shown in the 'Date' column of the 'device view coming from the clock on the computer Calibre is installed or the clock on the device? Both should show the same time as both are reporting the correct (identical) network time...

Thanks for any help or suggestions

kovidgoyal · 05-05-2020, 09:48 PM

It comes from the last modified timestamp of the files on the device. It will show 1970 if that timestamp is zero, which typically happens because of firmware issues on the device.

theducks · 05-05-2020, 10:19 PM

None of my dedicated readers have any Time Zone setting.
So, while the clock may show current time. The Library will have Locale adjusted Time
eg.<dc:date>2011-06-07T04:00:00+00:00</dc:date>

otta56 · 05-06-2020, 12:27 PM

Thank you for the replies.

It would appear that the Boox NotePro firmware I have tested from versions 2.2.1, 2.2.2 through 2.3 all have a bug related to the timestamp displayed in the device 'Date' column of Calibre 4.1.5.

maraskan_user · 03-30-2021, 09:11 AM

Sorry for resurrecting this, but I was wondering about something.

I'm accessing an Onyx Boox Nova3 via USB from Calibre 5.14 from Windows 10 and also noticed the Date column in Device view being 01 Jan 1970. The weird thing is, when displaing the same files on the device in Win10's file manager, is shows correct dates/times in a its "Changed" column, and empty fields in its "Created" column.

So it looks like the Nova3 actually does correctly track the timestamps and is able to return it to other devices when asked in certain ways. The question is, what is Win10's file manager doing differently than Calibre when asking the device for the files' timestamps...

(What's also slightly curious is that within its own file system, Win10 calls the columns "Change Date" and "Creation Date" instead of the "Changed" and "Created" with the connected Nova3.)

maraskan_user · 03-30-2021, 12:18 PM

One more thing:
The "Created" column is not empty on my Samsung phone, so this differs from my Nova3. Is Calibre's device view timestamp supposed to contain the creation or the lastchanged date?

05-05-2020, 04:23 PM	#1
otta56 Junior Member Posts: 8 Karma: 10 Join Date: Apr 2020 Device: Max Lumi 2	Source of 'timestamp' Data in "Device" 'Date' Column Hello, Using Calibre version 4.15 to export book files and metadata to 'device' always results in the device date column showing '31 Dec 1970'. Calibre always shows the time the book was first loaded into the calibre library. The clock time on the device and computer are correct and synchronized with NTP. So the question I have is where is the timestamp data shown in the 'Date' column of the 'device view coming from the clock on the computer Calibre is installed or the clock on the device? Both should show the same time as both are reporting the correct (identical) network time... Thanks for any help or suggestions

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05-05-2020, 09:48 PM	#2
kovidgoyal creator of calibre Posts: 45,265 Karma: 27110894 Join Date: Oct 2006 Location: Mumbai, India Device: Various	It comes from the last modified timestamp of the files on the device. It will show 1970 if that timestamp is zero, which typically happens because of firmware issues on the device.

05-05-2020, 10:19 PM	#3
theducks Well trained by Cats Posts: 30,971 Karma: 60358908 Join Date: Aug 2009 Location: The Central Coast of California Device: Kobo Libra2,Kobo Aura2v1, K4NT(Fixed: New Bat.), Galaxy Tab A	None of my dedicated readers have any Time Zone setting. So, while the clock may show current time. The Library will have Locale adjusted Time eg.<dc:date>2011-06-07T04:00:00+00:00</dc:date>

05-06-2020, 12:27 PM	#4
otta56 Junior Member Posts: 8 Karma: 10 Join Date: Apr 2020 Device: Max Lumi 2	Thank you for the replies. It would appear that the Boox NotePro firmware I have tested from versions 2.2.1, 2.2.2 through 2.3 all have a bug related to the timestamp displayed in the device 'Date' column of Calibre 4.1.5.

03-30-2021, 09:11 AM	#5
maraskan_user Member Posts: 12 Karma: 10 Join Date: Dec 2020 Location: Germany Device: Boox Nova 3, Galaxy Tab S6, Samsung M21	Sorry for resurrecting this, but I was wondering about something. I'm accessing an Onyx Boox Nova3 via USB from Calibre 5.14 from Windows 10 and also noticed the Date column in Device view being 01 Jan 1970. The weird thing is, when displaing the same files on the device in Win10's file manager, is shows correct dates/times in a its "Changed" column, and empty fields in its "Created" column. So it looks like the Nova3 actually does correctly track the timestamps and is able to return it to other devices when asked in certain ways. The question is, what is Win10's file manager doing differently than Calibre when asking the device for the files' timestamps... (What's also slightly curious is that within its own file system, Win10 calls the columns "Change Date" and "Creation Date" instead of the "Changed" and "Created" with the connected Nova3.)

03-30-2021, 12:18 PM	#6
maraskan_user Member Posts: 12 Karma: 10 Join Date: Dec 2020 Location: Germany Device: Boox Nova 3, Galaxy Tab S6, Samsung M21	One more thing: The "Created" column is not empty on my Samsung phone, so this differs from my Nova3. Is Calibre's device view timestamp supposed to contain the creation or the lastchanged date?

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