Subject: Re: bug#27651: grep.1: macro `Dt' not defined
From: Paul Eggert <[email-masked]>
To: "Santiago R.R." <[email-masked]>, [email-masked]
Date: Tue, 11 Jul 2017 08:24:49 -0700
List-Id: <debbugs-submit.debbugs.gnu.org>

Thanks for the bug report. I installed the attached patch. It uses a 
hand-maintained date, which is more likely to give the user the (accurate) 
impression that the grep man page is not the focus of our documentation efforts.
From 8d1953300ef03d05fb3864d944d1de81613a9bb6 Mon Sep 17 00:00:00 2001
From: Paul Eggert <[email-masked]>
Date: Tue, 11 Jul 2017 08:20:26 -0700
Subject: [PATCH] doc: define Dt string in man page

Problem reported by Bjarni I. Gislason via Santiago R.R. (Bug#27651).
* doc/grep.in.1 (dT): New macro.
(Dt): Define this string.
---
 doc/grep.in.1 | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/doc/grep.in.1 b/doc/grep.in.1
index 40c9586..ecc8105 100644
--- a/doc/grep.in.1
+++ b/doc/grep.in.1
@@ -1,4 +1,14 @@
 .\" GNU grep man page
+.de dT
+.ds Dt \\$2
+..
+.dT Time-stamp: "2017-06-21"
+.\" Update the above date whenever a change to either this file or
+.\" grep.c's 'usage' function results in a nontrivial change to the man page.
+.\" In Emacs, you can update the date by running 'M-x time-stamp'
+.\" after you make a change that you decide is nontrivial.
+.\" It is no big deal to forget to update the date.
+.
 .if !\n(.g \{\
 .	if !\w|\*(lq| \{\
 .		ds lq ``
@@ -1213,3 +1223,8 @@ This man page is maintained only fitfully;
 the full documentation is often more up-to-date.
 .\" Work around problems with some troff -man implementations.
 .br
+.
+.\" Format for Emacs-maintained Dt string defined at this file's start.
+.\" Local variables:
+.\" time-stamp-format: "%:y-%02m-%02d"
+.\" End:
-- 
2.7.4