From 15bdea6a19e600d83ae83def9974ce7b55fbd603 Mon Sep 17 00:00:00 2001
From: mrg <mrg@NetBSD.org>
Date: Sat, 3 Dec 2016 03:26:27 +0000
Subject: [PATCH] add a basic "-b" option - that outputs one display and exits.
 inspired by "top -b".  still requires a curses-capable output without some
 fairly significant internal restructuring.

---
 usr.bin/systat/main.c   | 17 ++++++++++++-----
 usr.bin/systat/systat.1 | 13 ++++++++++---
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/usr.bin/systat/main.c b/usr.bin/systat/main.c
index 0a92ab06158e..426755b2e418 100644
--- a/usr.bin/systat/main.c
+++ b/usr.bin/systat/main.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: main.c,v 1.50 2016/10/22 22:02:55 christos Exp $	*/
+/*	$NetBSD: main.c,v 1.51 2016/12/03 03:26:27 mrg Exp $	*/
 
 /*-
  * Copyright (c) 1980, 1992, 1993
@@ -36,7 +36,7 @@ __COPYRIGHT("@(#) Copyright (c) 1980, 1992, 1993\
 #if 0
 static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/6/93";
 #endif
-__RCSID("$NetBSD: main.c,v 1.50 2016/10/22 22:02:55 christos Exp $");
+__RCSID("$NetBSD: main.c,v 1.51 2016/12/03 03:26:27 mrg Exp $");
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -96,6 +96,7 @@ main(int argc, char **argv)
 	const char *all;
 	struct clockinfo clk;
 	size_t len;
+	int bflag = 0;
 
 	all = "all";
 	egid = getegid();
@@ -120,6 +121,9 @@ main(int argc, char **argv)
 			if ((turns = atoi(optarg)) <= 0)
 				errx(1, "turns <= 0.");
 			break;
+		case 'b':
+			bflag = !bflag;
+			break;
 		case '?':
 		default:
 			usage();
@@ -226,9 +230,12 @@ main(int argc, char **argv)
 	dellave = 0.0;
 
 	display(0);
-	noecho();
-	cbreak();
-	keyboard();
+	if (!bflag) {
+		noecho();
+		cbreak();
+		keyboard();
+	} else
+		die(0);
 	/*NOTREACHED*/
 }
 
diff --git a/usr.bin/systat/systat.1 b/usr.bin/systat/systat.1
index 14897ae1fb3b..15c246c060fd 100644
--- a/usr.bin/systat/systat.1
+++ b/usr.bin/systat/systat.1
@@ -1,4 +1,4 @@
-.\"	$NetBSD: systat.1,v 1.46 2016/08/03 13:09:43 wiz Exp $
+.\"	$NetBSD: systat.1,v 1.47 2016/12/03 03:26:27 mrg Exp $
 .\"
 .\" Copyright (c) 1985, 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -29,7 +29,7 @@
 .\"
 .\"	@(#)systat.1	8.2 (Berkeley) 12/30/93
 .\"
-.Dd August 2, 2016
+.Dd November 16, 2016
 .Dt SYSTAT 1
 .Os
 .Sh NAME
@@ -37,7 +37,7 @@
 .Nd display system statistics in a full-screen view
 .Sh SYNOPSIS
 .Nm
-.Op Fl n
+.Op Fl bn
 .Op Fl M Ar core
 .Op Fl N Ar system
 .Op Fl t Ar turns
@@ -94,6 +94,8 @@ Extract the name list from
 .Ar system
 instead of the default
 .Pa /netbsd .
+.It Fl b
+Show the chosen display once and exit.
 .It Fl n
 Do not resolve IP addresses into string hostnames
 .Pq FQDNs
@@ -626,3 +628,8 @@ The
 .Ic vmstat
 display looks out of place because it is (it was added in as
 a separate display from what used to be a different program).
+.Pp
+The
+.Fl b
+option requires a real terminal and could be converted to
+simply output to standard output.