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From: Farhan Khan <khanzf@gmail.com>
To: git@vger.kernel.org
Subject: Understanding pack format
Date: Fri, 2 Nov 2018 01:23:15 -0400	[thread overview]
Message-ID: <CAFd4kYBDWMvVgDmNTzwOK9Q7n_Fb0NrvNAFgHtKvkLkRFWqUKw@mail.gmail.com> (raw)

Hi all,

I am trying to understand the pack file format and have been reading
the documentation, specifically https://git-scm.com/docs/pack-format
(which is in git's own git repository as
"Documentation/technical/pack-format.txt"). I see that the file starts
with the "PACK" signature, followed by the 4 byte version and 4 byte
number of objects. After this, the documentation speaks about
Undeltified and Deltified representations. I understand conceptually
what each is, but do not know specifically how git parses it out.

Can someone please explain this to me? Is there any sample code of how
to interpret each entry? Where is this in the git code? That might
serve as a good guide.

I see a few references to "PACK_SIGNATURE", but not certain which
actually reads the data.

Thanks!
--
Farhan Khan
PGP Fingerprint: B28D 2726 E2BC A97E 3854 5ABE 9A9F 00BC D525 16EE

             reply	other threads:[~2018-11-02  5:23 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-02  5:23 Farhan Khan [this message]
2018-11-02  6:15 ` Understanding pack format Junio C Hamano
2018-11-02 16:00   ` Duy Nguyen
2018-11-06  2:23     ` Farhan Khan
2018-11-06  6:09       ` Jeff King
2018-11-06 16:06       ` Duy Nguyen
2018-11-02 15:54 ` Duy Nguyen

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