Re: [PATCH 1/2] lib-rebase.sh: fake-editor.sh: Allow checking of non-comment lines in $GIT_EDITOR

Nazri Ramliy [off-list ref] writes:

+			sed -i "s/^\([a-z]\+\) [0-9a-f]\+ /\1 $REPLACE_COMMIT_ID /" \

This is not portable. Escaping an ERE element with a backslash does not
make it suitable for use in BRE that sed uses.

Do we use in-place replacement anywhere else with sed?  I don't think it
is portable, either.