Reorder pieces of header in perl scripts.

The desired order is
- Prologue part 1 (2 lines with #!)
- Program short description
- Copyright and license notice
- Written-by notice
- Program short description (optional)
- Program long description (optional)
- Prologue part 2
- Time stamp
- Code

Reported by Paul Eggert.

* build-aux/announce-gen: Reorder header.
* build-aux/gitlog-to-changelog: Likewise.
* build-aux/useless-if-before-free: Likewise.
* build-aux/prefix-gnulib-mk: Add copyright notice and short
description.
* build-aux/update-copyright: Likewise. Add short description. Bump
time-stamp-line-limit to 200.

1 files changed, 26 insertions, 1 deletions

diff --git a/build-aux/prefix-gnulib-mk b/build-aux/prefix-gnulib-mk
index f3ca725174..445d91610e 100755
--- a/build-aux/prefix-gnulib-mk
+++ b/build-aux/prefix-gnulib-mk
@@ -1,5 +1,25 @@
 #!/bin/sh
 #! -*-perl-*-
+
+# Rewrite a gnulib.mk, adding prefixes to work with automake's subdir-objects.
+
+# Copyright (C) 2012-2019 Free Software Foundation, Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+#
+# Written by Jim Meyering
+
 # This is a prologue that allows to run a perl script as an executable
 # on systems that are compliant to a POSIX version before POSIX:2017.
 # On such systems, the usual invocation of an executable through execlp()
@@ -15,12 +35,17 @@
 eval 'exec perl -wSx "$0" "$@"'
      if 0;
 
+my $VERSION = '2012-01-21 17:13'; # UTC
+# The definition above must lie within the first 8 lines in order
+# for the Emacs time-stamp write hook (at end) to update it.
+# If you change this file with Emacs, please let the write hook
+# do its job.  Otherwise, update this string manually.
+
 use strict;
 use IO::File;
 use Getopt::Long;
 use File::Basename; # for dirname
 
-my $VERSION = '2012-01-21 17:13'; # UTC
 (my $ME = $0) =~ s|.*/||;
 
 my $prefix;