GNU bug report logs - #35043
Is there a way to show file name once just before all the matches in the file?

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Peng Yu <pengyu.ut <at> gmail.com>
To: bug-grep <at> gnu.org
Subject: Is there a way to show file name once just before all the matches in
 the file?
Date: Fri, 29 Mar 2019 15:47:41 -0500

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

Message #8 received at submit <at> debbugs.gnu.org (full text, mbox):

From: "Paul Jackson" <pj <at> usa.net>
To: bug-grep <at> gnu.org
Subject: Re: bug#35043: Is there a way to show file name once just before all the	matches in the file?
Date: Fri, 29 Mar 2019 23:01:48 -0400

[Message part 1 (text/plain, inline)]

The following awk command will do this (so long as filenames don't have ':' colon chars):

grep IP /etc/protocols /etc/services |
 awk -F: '
 $1 != fname { print $1 ":"; fname = $1; }
 { sub("^[^:]*:", ""); print; }
 '

-- 
 Paul Jackson
 pj <at> usa.net

[Message part 2 (text/html, inline)]

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