From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 334101F453 for ; Fri, 2 Nov 2018 15:55:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727696AbeKCBCr (ORCPT ); Fri, 2 Nov 2018 21:02:47 -0400 Received: from mail-io1-f44.google.com ([209.85.166.44]:45678 "EHLO mail-io1-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727277AbeKCBCr (ORCPT ); Fri, 2 Nov 2018 21:02:47 -0400 Received: by mail-io1-f44.google.com with SMTP id p83-v6so1679061iod.12 for ; Fri, 02 Nov 2018 08:55:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=jKbFLOgVvIb3vFtBAnQXjkR0qnR1Ka3BMT1zY6SaUUA=; b=AbWA6dcqJ367Ys3j+eexl7ZG/M4LHe4ZZwxerB79fYSIOEbXhGP1NAGVpWt/AfKhlj F8VLRseO9G1D7x5YNBtFRXdh4tiKRDiU+0CnFvcoamYnDiNO8QPx8ErSLayAAPv+hPVs 1qOhi++K1dDR1F/1S9OsVC/95iyP5OxfTl6h7RJSg4+UXAKWdquQOQfv26L0R1bTEOMN vaHQ638iag589+KkZ4hQMoasIjZ8yXcB1b283yQ5LO5k+ywO0CXXEIClEzDY+PuxOVgy KSoV5dHL/upcA+EAKMAA3wOmJtVZpfW7qiD2cae/UHlZJfr09KlMqu85AS9E5sgsccyw 5Ndw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=jKbFLOgVvIb3vFtBAnQXjkR0qnR1Ka3BMT1zY6SaUUA=; b=EbpkeX3MHjk5b5tOaLTtIMTKpmT2HUjBA4SPRMoP+6amA1pDQMouFCOd/YUKRv24/L NcByFUBBCjpfz4zXeOP4GsF0rDzvqJBDaugb9NGrW7X4ob4n434r2vnE/sxZX88gYzbv kHJ5+9gqL6LUlSOvoMDNfN2+6srkterPrZADLc8wbRbBB3ehcmv0NRLruo/s2J1Ie+kX aerGby5kCMPc/fUR1g6eyB9tpWoq9s/HobPJgoEOhSf83pfCUhJNPeH4sXve31sMG9Bk LNsZxpafEudGXmRjra66cGf0eaUDf4J+hj4NiqySEcKxhPj497/g432kB+oYJtFBrpYF vveA== X-Gm-Message-State: AGRZ1gJ/tNaBwUKXrrKQEXF36oB/EGIk7RbWoh/KeXEC7sHGRhukm6TW aEcovJi/jjV/q60PofXDk0OFRM+OJ1jooXyusbW1ag== X-Google-Smtp-Source: AJdET5dI38Su62961wceGD79NDSm6UpKl0o3shCQ+H/mZqmwl1PrQ7ITf2meGelpc9f8VgrmmW59+NbAsMDzI2lspyc= X-Received: by 2002:a6b:6f06:: with SMTP id k6-v6mr7986635ioc.236.1541174113597; Fri, 02 Nov 2018 08:55:13 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Duy Nguyen Date: Fri, 2 Nov 2018 16:54:46 +0100 Message-ID: Subject: Re: Understanding pack format To: khanzf@gmail.com Cc: Git Mailing List Content-Type: text/plain; charset="UTF-8" Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Fri, Nov 2, 2018 at 6:26 AM Farhan Khan wrote: > > 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. If by "it" you mean the deltified representations, I think it's actually documented in pack-format.txt. If you prefer C over English, look at patch-delta.c -- Duy