Mention related kernel options where applicable.

lib/libc/gen/sysconf.3

@@ -1,4 +1,4 @@
-.\"	$NetBSD: sysconf.3,v 1.25 2003/05/01 13:58:03 wiz Exp $
+.\"	$NetBSD: sysconf.3,v 1.26 2003/07/09 13:35:08 kleink Exp $
 .\"
 .\" Copyright (c) 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -33,7 +33,7 @@
 .\"
 .\"	@(#)sysconf.3	8.3 (Berkeley) 4/19/94
 .\"
-.Dd February 2, 2003
+.Dd July 9, 2003
 .Dt SYSCONF 3
 .Os
 .Sh NAME
@@ -139,6 +139,12 @@ and its
 Semaphores
 option to which the system attempts to conform,
 otherwise \-1.
+.Pp
+Availability of the
+Semaphores
+option depends on the
+.Li P1003_1B_SEMAPHORE
+kernel option. 
 .It Li _SC_SPIN_LOCKS
 The version of
 .St -p1003.1
@@ -176,8 +182,18 @@ otherwise \-1.
 The version of ISO/IEC 9945 (POSIX 1003.1) with which the system
 attempts to comply.
 .It Li _SC_XOPEN_SHM
-Return 1 of the system supports System V style shared memory,
+Return 1 if the the
+.St -xpg4.2
+Shared Memory
+option is available on this system,
 otherwise \-1.
+.Pp
+Availability of the
+Shared Memory
+option depends on the
+.Li SYSVSHM
+kernel option. 
+.It Li _SC_SPIN_LOCKS
 .It Li _SC_BC_BASE_MAX
 The maximum ibase/obase values in the
 .Xr bc 1