The patch below changes sysctl(8) to not require the -w flag when setting
a variable. Just "sysctl foo=var" is really enough.  Inspired by FreeBSD.

Any objections to commit?


 - Hubert

Index: sbin/sysctl/sysctl.8
===================================================================
RCS file: /cvsroot/basesrc/sbin/sysctl/sysctl.8,v
retrieving revision 1.74
diff -u -r1.74 sysctl.8
--- sbin/sysctl/sysctl.8	2002/02/08 01:30:47	1.74
+++ sbin/sysctl/sysctl.8	2002/03/04 03:26:30
@@ -33,7 +33,7 @@
 .\"
 .\"	@(#)sysctl.8	8.1 (Berkeley) 6/6/93
 .\"
-.Dd June 6, 1993
+.Dd March 4, 2002
 .Dt SYSCTL 8
 .Os
 .Sh NAME
@@ -41,12 +41,9 @@
 .Nd get or set kernel state
 .Sh SYNOPSIS
 .Nm sysctl
-.Op Fl n
-.Ar name ...
 .Nm sysctl
 .Op Fl n
-.Fl w
-.Ar name Ns Li = Ns Ar value ...
+.Ar name[=value] ...
 .Nm sysctl
 .Op Fl n
 .Fl a
@@ -88,9 +85,7 @@
 .Pp
 If just a MIB style name is given,
 the corresponding value is retrieved.
-If a value is to be set, the
-.Fl w
-flag must be specified and the MIB name followed
+If a value is to be set, the MIB name must be followed
 by an equal sign and the new value to be used.
 .Pp
 The
@@ -105,10 +100,6 @@
 .Ar name
 or
 .Ar name Ns Li = Ns Ar value .
-The
-.Fl w
-flag is implied by
-.Fl f .
 .Pp
 The
 .Ql proc
@@ -416,7 +407,7 @@
 To set the maximum number of processes allowed
 in the system to 1000, one would use the following request:
 .Bd -literal -offset indent -compact
-sysctl -w kern.maxproc=1000
+sysctl kern.maxproc=1000
 .Ed
 .Pp
 Information about the system clock rate may be obtained with:
@@ -439,11 +430,11 @@
 .Pp
 To redirect core dumps to the /var/tmp/\*[Lt]username\*[Gt] directory,
 .Bd -literal -offset indent -compact
-sysctl -w proc.$$.corename=/var/tmp/%u/%n.core
+sysctl proc.$$.corename=/var/tmp/%u/%n.core
 .Ed
 Shall be used.
 .Bd -literal -offset indent -compact
-sysctl -w proc.curproc.corename=/var/tmp/%u/%n.core
+sysctl proc.curproc.corename=/var/tmp/%u/%n.core
 .Ed
 changes the value for the sysctl process itself, and will not have the desired
 effect.
Index: sbin/sysctl/sysctl.c
===================================================================
RCS file: /cvsroot/basesrc/sbin/sysctl/sysctl.c,v
retrieving revision 1.55
diff -u -r1.55 sysctl.c
--- sbin/sysctl/sysctl.c	2002/01/31 20:15:14	1.55
+++ sbin/sysctl/sysctl.c	2002/03/04 03:26:31
@@ -152,7 +152,7 @@
 	{ 0, 0},
 };
 
-int	Aflag, aflag, nflag, wflag;
+int	Aflag, aflag, nflag;
 
 /*
  * Variables requiring special processing.
@@ -212,7 +212,6 @@
 
 		case 'f':
 			fn = optarg;
-			wflag = 1;
 			break;
 
 		case 'n':
@@ -220,7 +219,7 @@
 			break;
 
 		case 'w':
-			wflag = 1;
+			/* ignored - keep for backward compatibility */
 			break;
 
 		default:
@@ -305,8 +304,6 @@
 	bufp = buf;
 	snprintf(buf, BUFSIZ, "%s", string);
 	if ((cp = strchr(string, '=')) != NULL) {
-		if (!wflag)
-			errx(2, "Must specify -w to set variables");
 		*strchr(buf, '=') = '\0';
 		*cp++ = '\0';
 		while (isspace((unsigned char) *cp))
@@ -1158,7 +1155,7 @@
 	(void)fprintf(stderr,
 	    "Usage:\t%s %s\n\t%s %s\n\t%s %s\n\t%s %s\n\t%s %s\n",
 	    progname, "[-n] variable ...", 
-	    progname, "[-n] -w variable=value ...",
+	    progname, "[-n] variable=value ...",
 	    progname, "[-n] -a",
 	    progname, "[-n] -A",
 	    progname, "[-n] -f file");
Index: etc/rc.d/network
===================================================================
RCS file: /cvsroot/basesrc/etc/rc.d/network,v
retrieving revision 1.33
diff -u -r1.33 network
--- etc/rc.d/network	2001/07/22 13:33:59	1.33
+++ etc/rc.d/network	2002/03/04 03:26:31
@@ -119,8 +119,8 @@
 		#
 		route add -inet6 ::0.0.0.0 -prefixlen 96 ::1 -reject
 
-		sysctl -w net.inet6.ip6.forwarding=0 >/dev/null
-		sysctl -w net.inet6.ip6.accept_rtadv=0 >/dev/null
+		sysctl net.inet6.ip6.forwarding=0 >/dev/null
+		sysctl net.inet6.ip6.accept_rtadv=0 >/dev/null
 
 		# backward compatibility
 		#
@@ -139,12 +139,12 @@
 		case $ip6mode in
 		router)
 			echo 'IPv6 mode: router'
-			sysctl -w net.inet6.ip6.forwarding=1 >/dev/null
+			sysctl net.inet6.ip6.forwarding=1 >/dev/null
 			;;
 
 		autohost)
 			echo 'IPv6 mode: autoconfigured host'
-			sysctl -w net.inet6.ip6.accept_rtadv=1 >/dev/null
+			sysctl net.inet6.ip6.accept_rtadv=1 >/dev/null
 			;;
 
 		host)	
Index: etc/rc.d/securelevel
===================================================================
RCS file: /cvsroot/basesrc/etc/rc.d/securelevel,v
retrieving revision 1.3
diff -u -r1.3 securelevel
--- etc/rc.d/securelevel	2002/03/01 17:58:00	1.3
+++ etc/rc.d/securelevel	2002/03/04 03:26:31
@@ -25,12 +25,12 @@
 			exit 1
 		else
 			echo -n "Setting securelevel: "
-			sysctl -w kern.securelevel=$securelevel
+			sysctl kern.securelevel=$securelevel
 		fi
 	else
 		if [ "$osecurelevel" = 0 ]; then
 			echo -n "Setting securelevel: "
-			sysctl -w kern.securelevel=1
+			sysctl kern.securelevel=1
 		fi
  	fi
 }
Index: etc/rc.d/sysctl
===================================================================
RCS file: /cvsroot/basesrc/etc/rc.d/sysctl,v
retrieving revision 1.9
diff -u -r1.9 sysctl
--- etc/rc.d/sysctl	2000/08/21 23:31:24	1.9
+++ etc/rc.d/sysctl	2002/03/04 03:26:31
@@ -19,7 +19,7 @@
 *** WARNING: /etc/rc.conf \$defcorename setting is obsolete. Please
 *** set kern.defcorename in /etc/sysctl.conf
 __EOF__
-		sysctl -w kern.defcorename=$defcorename
+		sysctl kern.defcorename=$defcorename
 	fi
 
 	if [ -n "$nfsiod_flags" ]; then

-- 
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