improve ntpctl usage so that the manual page does not need to be read

every time
ok jmc

src/usr.sbin/ntpd/ntpctl.8

@@ -1,4 +1,4 @@
-.\" $OpenBSD: ntpctl.8,v 1.4 2013/10/16 21:23:59 jmc Exp $
+.\" $OpenBSD: ntpctl.8,v 1.5 2014/01/10 22:54:12 deraadt Exp $
 .\"
 .\" Copyright (c) 2012 Mike Miller <mmiller@mgm51.com>
 .\"
@@ -14,7 +14,7 @@
 .\" AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 .\" OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: October 16 2013 $
+.Dd $Mdocdate: January 10 2014 $
 .Dt NTPCTL 8
 .Os
 .Sh NAME
@@ -22,7 +22,7 @@
 .Nd control the Network Time Protocol daemon
 .Sh SYNOPSIS
 .Nm ntpctl
-.Op Fl s Ar modifier
+.Op Fl s Cm all | peers | sensors | status
 .Sh DESCRIPTION
 The
 .Nm
@@ -32,25 +32,21 @@ daemon.
 .Pp
 The options are as follows:
 .Bl -tag -width "-s modifierX"
-.It Fl s Ar modifier
-Show the data specified by
-.Ar modifier :
-.Bl -tag -width "sensorsXXX"
-.It Cm all
+.It Fl s Cm all
 Show all data.
-.It Cm peers
+.It Fl s Cm peers
 Show the following information about each peer: weight, trustlevel,
 stratum, number of seconds until the next poll, polling interval
 in seconds, and offset, network delay and network jitter in milliseconds.
 When the system clock is synced to a peer, an asterisk
 is displayed to the left of the weight column for that peer.
-.It Cm sensors
+.It Fl s Cm sensors
 Show the following information about each sensor: weight, sensor "good"
 status, stratum, and offset and the configured correction in
 milliseconds.
 When the system clock is synced to a sensor, an asterisk
 is displayed to the left of the weight column for that sensor.
-.It Cm status
+.It Fl s Cm status
 Show the status of peers and sensors, and whether the system clock is synced.
 When the system clock is synced, the stratum is displayed.
 When the system clock is not synced, the offset of the system clock,
@@ -58,7 +54,6 @@ as reported by the
 .Xr adjtime 2
 system call, is displayed.
 .El
-.El
 .Sh FILES
 .Bl -tag -width "/var/run/ntpd.sockXXX" -compact
 .It Pa /var/run/ntpd.sock

src/usr.sbin/ntpd/ntpd.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: ntpd.c,v 1.75 2013/11/13 20:44:39 benno Exp $ */
+/*	$OpenBSD: ntpd.c,v 1.76 2014/01/10 22:54:12 deraadt Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -81,7 +81,7 @@ usage(void)
 	extern char *__progname;
 
 	if (strcmp(__progname, "ntpctl") == 0)
-		fprintf(stderr, "usage: ntpctl [-s modifier]\n");
+		fprintf(stderr, "usage: ntpctl [-s all | peers | sensors | status]\n");
 	else
 		fprintf(stderr, "usage: %s [-dnSsv] [-f file]\n",
 		    __progname);