diff --git a/testcode/lib/atari/defdev.c b/testcode/lib/atari/defdev.c
new file mode 100644
index 000000000..717eaa4f3
--- /dev/null
+++ b/testcode/lib/atari/defdev.c
@@ -0,0 +1,18 @@
+/*
+ * testprogram printing the default device
+ *
+ * 26-Nov-2009, Christian Groessler
+ */
+
+#include <stdio.h>
+#include <conio.h>
+#include <atari.h>
+
+extern char _defdev[];
+
+int main(void)
+{
+	printf("default device: %s\n", _defdev);
+	if (_dos_type != SPARTADOS && _dos_type != OSADOS) cgetc();
+	return 0;
+}