From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Sixt <j.sixt@viscovery.net>
Subject: Re: [PATCH 1/2] rebase -i: optimize the creation of the todo file
Date: Thu, 08 Mar 2012 12:51:28 +0100
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To: Dominique Quatravaux <domq@google.com>
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Am 3/8/2012 12:41, schrieb Dominique Quatravaux:
> On Thu, Mar 8, 2012 at 12:36 PM, Dominique Quatravaux <domq@google.com> wrote:
>> On Thu, Mar 8, 2012 at 12:20 PM, Johannes Sixt <j.sixt@viscovery.net> wrote:
>>> Am 3/8/2012 11:42, schrieb Dominique Quatravaux:
>>>> +     shortsha1=$(echo $sha1 | cut -c1-7)
>>>
>>>> -             sha1=$(git rev-parse $shortsha1)
>>>
>>> Why do you call it "optimization" when you spend two or three subprocesses
>>> instead of one?
>>
>> echo is a shell internal. "git rev-parse" is two processes just as
>> "cut" and a pipe.
> 
> My mistake, strace git rev-parse revals that this is only one process.
> Still, I think that saving a bunch of filesystem access beats saving
> one fork()... 

Not so on Windows.

But you must look at the repository in any case to avoid truncating the
SHA1 too much, as Thomas pointed out.

-- Hannes