Provide some examples for watchdogd usage.

usr.sbin/watchdogd/watchdogd.8

@@ -27,7 +27,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd March 5, 2013
+.Dd July 27, 2013
 .Dt WATCHDOGD 8
 .Os
 .Sh NAME
@@ -204,6 +204,81 @@ and the kernel
 .Xr log 4
 device for
 .Xr syslog 8 .
+.Sh EXAMPLES
+.Ss Debugging watchdogd and/or your watchdog script.
+.Pp
+This is a useful recipe for debugging watchdogd and your watchdog
+script.
+.Pp
+(Note that ^C works oddly because watchdogd calls system(3) so the
+first ^C will terminate the "sleep" command.)
+.Pp
+.Pp
+Explanation of options used:
+.Bl -enum -offset indent -compact
+.It
+Set Debug on (--debug)
+.It
+Set the watchdog to trip at 30 seconds. (-t 30)
+.It
+Use of a softtimeout:
+.Bl -enum -offset indent -compact -nested
+.It
+Use a softtimeout (don't arm the hardware watchdog) (--softtimeout)
+.It
+Set the softtimeout action to do both kernel printf(9) and log(9) when it trips. (--softtimeout-action log,printf)
+.El
+.It
+Use of a pre-timeout:
+.Bl -enum -offset indent -compact -nested
+.It
+Set a pre-timeout of 15 seconds (this will later trigger a panic/dump) (--pretimeout 15)
+.It
+Set the action to also kernel printf(9) and log(9) when it trips. (--pretimeout-action log,printf)
+.El
+.It
+Use of a script:
+.Bl -enum -offset indent -compact -nested
+.It
+Run "sleep 60" as a shell command that acts as the watchdog (-e 'sleep 60')
+.It
+Warn us when the script takes longer than 1 second to run (-w)
+.El
+.El
+.Bd -literal
+watchdogd --debug -t 30 \\
+  --softtimeout --softtimeout-action log,printf \\
+  --pretimeout 15 --pretimeout-action log,printf \\
+  -e 'sleep 60' -w
+.Ed
+.Ss Production use of example
+.Bl -enum -offset indent -compact
+.It
+Set hard timeout to 120 seconds (-t 120)
+.It
+Set a panic to happen at 60 seconds (to trigger a
+.Xr crash 8
+for dump analysis):
+.Bl -enum -offset indent -compact -nested
+.It
+Use of pre-timeout (--pretimeout 60)
+.It
+Specify pre-timeout action (--pretimeout-action log,printf,panic )
+.El
+.It
+Use of a script:
+.Bl -enum -offset indent -compact -nested
+.It
+Run your script (-e '/path/to/your/script 60')
+.It
+Log if your script takes a longer than 15 seconds to run time. (-w -T 15)
+.El
+.El
+.Bd -literal
+watchdogd  -t 120 \\
+  --pretimeout 60 --pretimeout-action log,printf,panic \\
+  -e '/path/to/your/script 60' -w -T 15
+.Ed
 .Sh FILES
 .Bl -tag -width ".Pa /var/run/watchdogd.pid" -compact
 .It Pa /var/run/watchdogd.pid