diff --git a/src/ex_cmds.h b/src/ex_cmds.h
index 16540bd..ac61f1a 100644
--- a/src/ex_cmds.h
+++ b/src/ex_cmds.h
@@ -304,7 +304,7 @@
 EX(CMD_display,		"display",	ex_display,
 			EXTRA|NOTRLCOM|TRLBAR|SBOXOK|CMDWIN),
 EX(CMD_diffupdate,	"diffupdate",	ex_diffupdate,
-			TRLBAR),
+			BANG|TRLBAR),
 EX(CMD_diffget,		"diffget",	ex_diffgetput,
 			RANGE|EXTRA|TRLBAR|MODIFY),
 EX(CMD_diffoff,		"diffoff",	ex_diffoff,