Re: [RFC] git checkout $tree -- $path always rewrites files

> On Fri, Nov 07, 2014 at 03:13:24AM -0500, Jeff King wrote:
>
>> I noticed that "git checkout $tree -- $path" will _always_ unlink and
>> write a new copy of each matching path, even if they are up-to-date with
>> the index and the content in $tree is the same.
>
> By the way, one other thing I wondered while looking at this code: when
> we checkout a working tree file, we unlink the old one and write the new
> one in-place. Is there a particular reason we do this versus writing to
> a temporary file and renaming it into place?  That would give
> simultaneous readers a more atomic view.
>
> I suspect the answer is something like: you cannot always do a rename,
> because you might have a typechange, directory becoming a file, or vice
> versa; so anyone relying on an atomic view during a checkout operation
> is already Doing It Wrong.  Handling a content-change of an existing
> path would complicate the code, so we do not bother.