Add wtmpcvt(1).

This utility allows users to convert their wtmp databases to the new
format. It makes no sense for users to keep their wtmp log files if they
are unable to view them.

It basically copies ut_line into ut_id as well. This makes it possible
for last(1) and ac(8) to match login records with their corresponding
logout record.

1 files changed, 3 insertions, 1 deletions

diff --git a/UPDATING b/UPDATING
index 98b8d95b93c6..fe27b4f87954 100644
--- a/UPDATING
+++ b/UPDATING
@@ -37,7 +37,9 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 9.x IS SLOW:
 
 	After the system has been upgraded, it is safe to remove the old
 	log files (/var/run/utmp, /var/log/lastlog and /var/log/wtmp*),
-	assuming their contents is of no importance anymore.
+	assuming their contents is of no importance anymore.  Old wtmp
+	databases can only be used by last(1) and ac(8) after they have
+	been converted to the new format using wtmpcvt(1).
 
 20100108:
 	Introduce the kernel thread "deadlock resolver" (which can be enabled