/usr/bin/nmzegrep is in namazu2 2.0.21-10.
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 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122  | #! /usr/bin/perl -w
# -*- Perl -*-
#
# nmzegrep - search namazu-indexed documents for a given pattern and 
#            print lines matching the pattern.
# 
# $Id: nmzegrep.in,v 1.4.2.3 2008-06-02 09:48:13 opengl2772 Exp $
#
# Copyright (C) 2004 Yukio USUDA All rights reserved.
# Copyright (C) 2004-2008 Namazu Project All rights reserved.
#     This is free software with ABSOLUTELY NO WARRANTY.
#
#  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 versions 2, 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., 59 Temple Place - Suite 330, Boston, MA
#  02111-1307, USA
#
use strict;
use English;
use FileHandle;
require 5.004;
my @opts = ();
while (defined $ARGV[0] && $ARGV[0] =~ /^-/) {
    push @opts, $ARGV[0];
    shift @ARGV;
}
if (@ARGV == 0) {
    print "usage: nmzegrep [egrep's options] <pattern> [index]...\n";
    exit 1;
}
my $pattern = shift @ARGV;
my @indices = @ARGV;
my $PKGDATADIR = $ENV{'pkgdatadir'} || "/usr/share/namazu";
my $LIBDIR     = $PKGDATADIR . "/pl";     # directory where library etc. are in.
my $Document = undef;
unshift @INC, $LIBDIR;
require "util.pl" || die "unable to require \"util.pl\"\n";
require "document.pl" || die "unable to require \"document.pl\"\n";
require "var.pl" || die "unable to require \"var.pl\"\n";
require "conf.pl" || die "unable to require \"conf.pl\"\n";
require "ext.pl" || die "unable to require \"ext.pl\"\n";
my $tmpdir = "/tmp/NMZ$$";
if ($English::OSNAME eq "MSWin32") {
    $tmpdir = "$ENV{'TMP'}/NMZ$$";
}
if (mkdir($tmpdir, 0700)) {
    $var::OUTPUT_DIR = $tmpdir;
} else {
    die "unable to make temporary directory \"$tmpdir\"\n";
}
util::set_lang();
if (util::islang("ja") && $conf::NKF =~ /^module_nkf/) {
    require NKF || die "unable to require \"NKF\"\n";
    util::dprint(_("code conversion: using NKF module\n"));
    $var::USE_NKF_MODULE = 1;
}
$Document = mknmz::document->new();
$Document->init();
my $command = "namazu -alR $pattern @indices";
my $fh = new FileHandle;
$fh->open("$command |");
if (defined $fh) {
    my ($uri, $fname);
    while ($fname = <$fh>) {
	chop $fname;
	my $content = util::readfile($fname);
	$Document->init_doc($uri, $fname, \$content, undef);
	my $contref= $Document->get_filtered_contentref();
	my $tmpfile  = util::tmpnam('NMZ.nmzgrep');
	{ 
	    my $fh = util::efopen("> $tmpfile");
	    print $fh $$contref;
	    $fh->close();
	}
	my $fh2 = new FileHandle;
	$fh2->open("egrep -h @opts $pattern $tmpfile |");
	my $line;
	while ($line = <$fh2>) {
	    my $options = join(" ", @opts);
	    unless ($options =~ /(-h|--no-filename)/){
		print "$fname:";
	    }
	    print $line;
	}
	$fh2->close();
	unlink $tmpfile;
    }
} else {
    die "nmzegrep: $!";
}
rmdir $tmpdir or die "unable to remove temporary directory \"$tmpdir\"\n";
exit 0;
muda(
    $var::USE_NKF_MODULE, $var::OUTPUT_DIR,
    $conf::NKF
    );
sub muda {};
 |