threads / discuss / 44179

Repeatable Extraction

Subject: Repeatable Extraction

## tl;dr

3 messages between Sep 28, 2016 and Oct 4, 2016.

replies: 2people: 3as markdown or json

chris king· Sep 28, 2016, 03:14 UTC · lore

Hello, first off thanks for such a wonderful tool! I have a general question and I hope this is an appropriate spot to ask it.

Is there a way automate extraction that will repeatably generate the same files? Currently, each time I extract git portable many of the binaries change slightly. For example, if I extract twice using

    PortableGit-2.10.0-32-bit.7z.exe -y -gm2

then Beyond Compare tells me that many of the files in usr\bin have changed at offset 0x88 and 0x89. Why is that?

Warm regards, Chris

Dennis Kaarsemaker· Sep 28, 2016, 06:49 UTC · re: chris king · lore

Re: Repeatable Extraction

On di, 2016-09-27 at 20:14 -0700, chris king wrote:

Show 11 quoted lines

> Hello, first off thanks for such a wonderful tool! I have a general
> question and I hope this is an appropriate spot to ask it.
> 
> Is there a way automate extraction that will repeatably generate the
> same files? Currently, each time I extract git portable many of the
> binaries change slightly. For example, if I extract twice using
> 
>     PortableGit-2.10.0-32-bit.7z.exe -y -gm2
> 
> then Beyond Compare tells me that many of the files in usr\bin have
> changed at offset 0x88 and 0x89. Why is that?

Hi Chris,

That file is specific to the git for windows project, not git itself. While you may be able to find somebody on the git@vger mailinglist who knows the answer, git for windows also has a separate mailinglist at https://groups.google.com/forum/#!forum/git-for-windows and a chat room at https://gitter.im/git-for-windows/git -- these may be of more assistance in this case.

-- 
Dennis Kaarsemaker
http://www.kaarsemaker.net

Johannes Schindelin· Oct 4, 2016, 10:25 UTC · re: chris king · lore

Re: Repeatable Extraction

Hi Chris,

On Tue, 27 Sep 2016, chris king wrote:

Show 8 quoted lines

> Is there a way automate extraction that will repeatably generate the
> same files? Currently, each time I extract git portable many of the
> binaries change slightly. For example, if I extract twice using
> 
>     PortableGit-2.10.0-32-bit.7z.exe -y -gm2
> 
> then Beyond Compare tells me that many of the files in usr\bin have
> changed at offset 0x88 and 0x89. Why is that?

The reason is that you look at 32-bit, where technical limitations force us to hard-code a certain base address for all of the includede MSYS2 .dll files (i.e. all libraries that require, or implement, the POSIX emulation layer called MSYS2).

To avoid clashes with other .dll files, that base address is adjusted via the post-install.bat script for your particular environment.

If you want to avoid that, you will have to extract the installer via 7-Zip: it is a self-extracting .7z archive (and the self-extractor automatically executes post-install.bat, which subsequently deletes itself).

Ciao, Johannes