/usr/sbin/update-lilo is in lilo 1:24.2-3.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32  | #!/bin/sh
#       update-lilo - execute lilo in special debconf mode
#
#       Copyright 2010-2012 Joachim Wiedorn <ad_debian at joonet.de>
#
#       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 2 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, write to the Free Software
#       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
#       MA 02110-1301, USA.
set -e
# Run the boot loader installer. Sending STDOUT to STDERR
# to avoid confusing debconf, which has redirected STDOUT.
if [ -f /etc/lilo.conf ]
then
   lilo  >&2
fi
# end of file
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