test/putsurface_x11.c: don't hard code the DISPLAY to ":0.0"

Signed-off-by: Austin Yuan <shengquan.yuan@gmail.com>

diff --git a/test/putsurface/putsurface_x11.c b/test/putsurface/putsurface_x11.c
index a89d914..db765af 100644 (file)
--- a/test/putsurface/putsurface_x11.c
+++ b/test/putsurface/putsurface_x11.c
@@ -41,7 +41,7 @@ static int check_window_event(void *x11_display, void *drawable, int *width, int
 
 static void *open_display(void)
 {
-    return XOpenDisplay(":0.0");
+    return XOpenDisplay(NULL);
 }
 
 static void close_display(void *win_display)