assist the clueless user (that was me) in discovering the current

format of their superblock, provide a pointer to 'dumpfs -s'

share/man/man4/wapbl.4

@@ -1,4 +1,4 @@
-.\"     $NetBSD: wapbl.4,v 1.6 2008/08/02 14:29:12 simonb Exp $
+.\"     $NetBSD: wapbl.4,v 1.7 2009/02/25 22:14:04 plunky Exp $
 .\"
 .\" Copyright (c) 2008 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -24,7 +24,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd July 21, 2008
+.Dd Feburary 25, 2009
 .Dt WAPBL 4
 .Os
 .Sh NAME
@@ -174,8 +174,12 @@ aware will not be able to deal with an in-filesystem log.
 .Pp
 .Nm
 requires the super block to be in the UFS2 format.
-Older FFSv1 file systems will need to be updated to the newer super block
-layout with the
+The super block format can be checked using the
+.Fl s
+option with
+.Xr dumpfs 8 ,
+and older FFSv1 file systems will need to be updated to the newer
+super block layout with the
 .Fl c
 option to
 .Xr fsck_ffs 8 .