From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: current repository hash
Date: Mon, 16 Jun 2008 11:04:17 -0400
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References: <556d90580806160451g36daefb6o48b93b92589211bf@mail.gmail.com>
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Cc: git@vger.kernel.org
To: Alf Clement <alf.clement@gmail.com>
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On Mon, Jun 16, 2008 at 01:51:52PM +0200, Alf Clement wrote:

> What would be the best command to get a unique identifier?

If you just want the commit sha1, then "git rev-list -1 HEAD" will give
it to you. But take a look at git-describe, which is designed to give a
nice human-readable name based on your tags.

> Do I need the 40 digit hash id?

No, but you increase your chances of a collision in the future. In
practice, 8 or 9 characters tends to give unique commits.

> How can I make sure that a shorter hash id will be unique?

git-describe will find the shortest unique hash. But bear in mind that
it may not be unique forever.

-Peff