/usr/bin/ae_diff2htm is in aegis-web 4.24.3-3.
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 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | #!/bin/sh
#
#	aegis - project change supervisor
#	Copyright (C) 2002, 2004, 2006, 2008 Peter Miller
#
#	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
#	<http://www.gnu.org/licenses/>.
#
#
# Work out if there is a diff2html program on the PATH.
# This can't be worked out by ./configure, because this happens on the
# machine which *builds* the RPM, and not the machine on which the rpm
# is installed.  Plus, they could run aeget in a chroot jail, and
# not put diff2html in the jail with it.
#
have_diff2html=no
IFS="${IFS=   }"
save_ifs="$IFS"; IFS=":"
dummy="$PATH"
for dir in $dummy
do
    test -z "$dir" && ac_dir=.
    if test -f $dir/diff2html
    then
	have_diff2html=yes
	break
    fi
done
IFS="$save_ifs"
#
# The command line should have two file names on it, diff them and output HTML.
#
if test "$have_diff2html" = "yes"
then
    diff2html "$@"
else
    echo '<pre>'
    diff -c "$@" 2>&1 | sed 's|<|\<|g'
    echo '</pre>'
fi
exit 0
 |