More code.

Change-Id: Ie53ea58b3d0e8e906a2e51752ecfbe1e434b4261
diff --git a/src/bin/tut4.rs b/src/bin/tut4.rs
new file mode 100644
index 0000000..f743435
--- /dev/null
+++ b/src/bin/tut4.rs
@@ -0,0 +1,9 @@
+// Fearless Concurrency
+
+#![allow(dead_code)]
+#![allow(unused_imports)]
+
+use rust_tutorial::*;
+
+fn main() {
+}