bug#35043: Is there a way to show file name once just before all the matches in the file?

[Peng Yu]

Hi,

By default, filenames are shown at the same lines of the matches (when
there are multiple files). But I'd like a filename only shown once
before all the matches in the given file. Is there an option to do so
with grep? Thanks.

-- 
Regards,
Peng