Re: Do the file timestamps in ISOs matter ?

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

i wrote:
> > All three possible behaviors lead to reproducibility if the
> > input trees of the ISO production runs are sufficiently
> > similar.

Sam Hartman wrote:
> So, are you using a definition of reproducible different than the
> resulting iso will have the same SHA-1 hash?

I mean identical results. Bit by bit.

The question to decide is:
What is considered a sufficiently similar input tree in respect to
timestamps ?

Or in the context of ISO producers:
How much flattening (non-injectivity) is tolerable. How much fidelity
(non-aliasing) is needed ?

The answer depends on the expectations of the programs inside the ISO
or expectations of programs and informations which get imported from
elsewhere by the programs in the ISO. (The expectations of already
installed software on the target system are restricted to those of
boot firmware, i assume.)

For example, assume that "make" is supposed to act on ISO content.
In that case, high timestamp fidelity would be needed.


Have a nice day :)

Thomas