Three bytes in a zip file

Larry Doolittle larry at
Fri Apr 7 17:09:31 UTC 2023

Michael -

On Fri, Apr 07, 2023 at 01:31:24PM +0200, Michael Schierl wrote:
> Larry's script already called touch immediately before zip. But I assume
> the nature of atime can mean that any other process may have "won the
> race" and accessed the file just in between these two lines.

That's my working assumption.  Also, the irreproducibility
did not reproduce.  Maybe it _is_ velocity-dependent.  ;-)

> The DOS timestamps encode only mtime, and not ctime or atime.

It does seem simpler and more reliable to keep atime out of it.

On Fri, Apr 07, 2023 at 01:25:04PM +0200, Michael Schierl wrote:
> When I distribute
> ZIP files, I often touch all files to UNIX epoch anyway as I don't want
> to leak the exact time I have built/compiled them.

Right.  Except the time I set them to here is the time of
the source git commit (SOURCE_DATE_EPOCH).

> Another option would be to use an UTC-12:00 timezone like TZ=Etc/GMT+12
> for building the .zip file to ensure the files are "old enough" for
> every place in the world.

That sounds too unexpected to me.  I'll stick to UTC.
In practice, I bet nobody will notice, and if they do, it's easy to explain.

  - Larry

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