diff --git a/README.md b/README.md
index c3bab060..503ef87d 100644
--- a/README.md
+++ b/README.md
@@ -215,10 +215,10 @@ To lock the orientation of the mirroring:
 
 ```bash
 scrcpy --lock-video-orientation     # initial (current) orientation
-scrcpy --lock-video-orientation 0   # natural orientation
-scrcpy --lock-video-orientation 1   # 90° counterclockwise
-scrcpy --lock-video-orientation 2   # 180°
-scrcpy --lock-video-orientation 3   # 90° clockwise
+scrcpy --lock-video-orientation=0   # natural orientation
+scrcpy --lock-video-orientation=1   # 90° counterclockwise
+scrcpy --lock-video-orientation=2   # 180°
+scrcpy --lock-video-orientation=3   # 90° clockwise
 ```
 
 This affects recording orientation.
diff --git a/app/tests/test_cli.c b/app/tests/test_cli.c
index 3fa9b3d7..94740a9a 100644
--- a/app/tests/test_cli.c
+++ b/app/tests/test_cli.c
@@ -51,7 +51,7 @@ static void test_options(void) {
         "--fullscreen",
         "--max-fps", "30",
         "--max-size", "1024",
-        "--lock-video-orientation", "2",
+        "--lock-video-orientation=2", // optional arguments require '='
         // "--no-control" is not compatible with "--turn-screen-off"
         // "--no-display" is not compatible with "--fulscreen"
         "--port", "1234:1236",