Re: How to use git attributes to configure server-side checks?

Michael Haggerty [off-list ref] writes:

I was just alerted by Scott Chacon's blog [1] to the fact that one can
set GIT_INDEX_FILE to an arbitrary filename, thereby causing the index
to be read/written from that file instead of $GIT_DIR/index.

That's very old fashioned.  For almost five years, the preferred way to
say that has been "git read-tree --index-output=file" ;-)

But what you outlined should work.