add option --concurrent
diff --git a/ebtables.8 b/ebtables.8
index d6269df..001aa35 100644
--- a/ebtables.8
+++ b/ebtables.8
@@ -404,6 +404,9 @@
 When talking to the kernel, use this
 .I program
 to try to automatically load missing kernel modules.
+.TP
+.B --concurrent
+Use a file lock to support concurrent scripts updating the ebtables kernel tables.
 
 .SS
 RULE SPECIFICATIONS