+ diff=$(diff -u $stats_path $tmp 2>&1 ||:)
+ printf "diff of: btrfs dev stats -c %s\n%s\n" "$mnt" "$diff"
+ exim -odf -i root <<EOF
+From: root@$(hostname -f)
+To: root@$(hostname -f)
+Subject: btrfsmaint: device stats changed for $mnt
+
+diff of: btrfs dev stats -c $mnt
+$diff
+EOF