diff --git a/src/template.c b/src/template.c
index 34eb1eb..7e7f341 100644
--- a/src/template.c
+++ b/src/template.c
@@ -217,7 +217,7 @@ main(void)
 	// 1. open file
 	FILE* output_file = fopen(OUTPUT_FILE,
 		"wb"
-#if REPEAT_TIMES > 0
+#if REPEAT_TIMES > 0 && SEQUENTIAL_MODE
 		"+"
 #endif
 		);