--- lsof_4.91/Configure	2018-02-14 09:18:55.000000000 -0500
+++ lsof_4.91/Configure	2018-09-12 17:48:25.269577168 -0400
@@ -2943,6 +2943,12 @@
       LSOF_CFGF="$LSOF_CFGF -DHASIPv6"
     fi	# }
 
+    if test -r ${LSOF_INCLUDE}/utmpx.h	# {
+    then
+      LSOF_CFGF="$LSOF_CFGF -DHASUTMPX"
+      LSOF_CFGL="$LSOF_CFGL -lutmps -lskarnet"
+    fi	# }
+
     # Test for <rpc/rpc.h>.
 
     if ! test -r ${LSOF_INCLUDE}/rpc/rpc.h	# {