1 files changed, 56 insertions, 0 deletions
diff --git a/third_party/rust/crossbeam-channel/examples/stopwatch.rs b/third_party/rust/crossbeam-channel/examples/stopwatch.rs
new file mode 100644
index 0000000000..3a7578e00d
--- /dev/null
+++ b/third_party/rust/crossbeam-channel/examples/stopwatch.rs
@@ -0,0 +1,56 @@
+//! Prints the elapsed time every 1 second and quits on Ctrl+C.
+
+#[cfg(windows)] // signal_hook::iterator does not work on windows
+fn main() {
+    println!("This example does not work on Windows");
+}
+
+#[cfg(not(windows))]
+fn main() {
+    use std::io;
+    use std::thread;
+    use std::time::{Duration, Instant};
+
+    use crossbeam_channel::{bounded, select, tick, Receiver};
+    use signal_hook::consts::SIGINT;
+    use signal_hook::iterator::Signals;
+
+    // Creates a channel that gets a message every time `SIGINT` is signalled.
+    fn sigint_notifier() -> io::Result<Receiver<()>> {
+        let (s, r) = bounded(100);
+        let mut signals = Signals::new(&[SIGINT])?;
+
+        thread::spawn(move || {
+            for _ in signals.forever() {
+                if s.send(()).is_err() {
+                    break;
+                }
+            }
+        });
+
+        Ok(r)
+    }
+
+    // Prints the elapsed time.
+    fn show(dur: Duration) {
+        println!("Elapsed: {}.{:03} sec", dur.as_secs(), dur.subsec_millis());
+    }
+
+    let start = Instant::now();
+    let update = tick(Duration::from_secs(1));
+    let ctrl_c = sigint_notifier().unwrap();
+
+    loop {
+        select! {
+            recv(update) -> _ => {
+                show(start.elapsed());
+            }
+            recv(ctrl_c) -> _ => {
+                println!();
+                println!("Goodbye!");
+                show(start.elapsed());
+                break;
+            }
+        }
+    }
+}