[lug] laptop time

Timothy C. Klein teece at silverklein.net
Fri Feb 23 10:25:35 MST 2001

On Fri, Feb 23, 2001 at 10:40:36AM -0500, John Karns wrote:
> What about the timestamps on the filesystem.  What I would't like is
> having to deal with GMT in the file timestamps.  I presume that cron would
> be referenced to the local time and not GMT - correct?

I believe time stamps are stored in GMT.  However, this is actually the
best way, if everyone uses GMT.  Every call to the kernel to give a user
the value of a time variable involves applying the local offset to that
time, so your files can all be time-stamped in GMT and you would never
know it.  The only way it could be a problem that I see is if you
regularly schlep files between machines that are set differently, ie one
hardware clock set to GMT, and the other not.  But even this could be
worked around, I suppose, it kinda kludgey.

The cool thing about storing them as GMT, though, is that the file you
create at 10:19 23 Feb 2001, will show that as the creation time to you,
but if you send that file, and preserve its setting, it will show your
friend in England that the file was created at 17:19 23 Feb 2001, and
your friend in Tokyo will see the file as created at 02:19 24 Feb 2001.
That is very nice, in this way *ALL* Linux kernels keep track of things
in one time frame.  It gets converted to local time for our benefit.
Very slick.  All machines should be REQUIRED to work this way.  Then
things like time stamps on mail and the like would always work

Also, your machine only looks at the hardware clock at bootup time, and
after a suspend  on a laptop (or a desktop).  From that point on the
kernel keeps its own clock.


> ----------------------------------------------------------------------
> John Karns                                              jkarns at csd.net
> _______________________________________________
> Web Page:  http://lug.boulder.co.us
> Mailing List: http://lists.lug.boulder.co.us/mailman/listinfo/lug

== Timothy Klein       || And what rough beast                   ==
== teece at hypermall.net || Its hour come round at last            ==
== Aufwiedersehen!     || Slouches towards Bethlehem to be born? ==
== Aufwiedersehen!     || The beast of Redmond, nothing more.    ==

More information about the LUG mailing list