Index: head/usr.bin/users/users.cc
===================================================================
--- head/usr.bin/users/users.cc	(revision 311580)
+++ head/usr.bin/users/users.cc	(revision 311581)
@@ -1,65 +1,72 @@
 /*-
  * Copyright (c) 2014 Pietro Cerutti <gahr@FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 
+#include <sys/capsicum.h>
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <err.h>
+#include <errno.h>
 #include <utmpx.h>
 
 #include <algorithm>
 #include <iostream>
 #include <iterator>
 #include <set>
 #include <string>
 using namespace std;
 
 int
 main(int argc, char **)
 {
 	struct utmpx *ut;
 	set<string> names;
 
 	if (argc > 1) {
 		cerr << "usage: users" << endl;
 		return (1);
 	}
 
 	setutxent();
+
+	if (cap_enter() < 0 && errno != ENOSYS)
+		err(1, "Failed to enter capability mode.");
+
 	while ((ut = getutxent()) != NULL)
 		if (ut->ut_type == USER_PROCESS)
 			names.insert(ut->ut_user);
 	endutxent();
 
 	if (!names.empty()) {
 		set<string>::iterator last = names.end();
 		--last;
 		copy(names.begin(), last, ostream_iterator<string>(cout, " "));
 		cout << *last << endl;
 	}
 }