Tokio ctrl_c handler doesn't fire

[arnie]

This code (tokio part) is taken verbatim from tokio's webpage. This is working example.

use tokio::{
    signal,
    sync::mpsc::{UnboundedReceiver, UnboundedSender},
};
async fn tokio_ctrl_c(shutdown_send: UnboundedSender<()>) {
    // ... spawn application as separate task ...
    //
    // application uses shutdown_send in case a shutdown was issued from inside
    // the application
    match signal::ctrl_c().await {
        Ok(()) => {
            eprintln!("aaaa");
            shutdown_send.send(()).unwrap();
        }
        Err(err) => {
            eprintln!("Unable to listen for shutdown signal: {}", err);
            shutdown_send.send(()).unwrap();
            // we also shut down in case of error
        }
    }
}

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let (shutdown_send, mut shutdown_recv) = tokio::sync::mpsc::unbounded_channel::<()>();

    tokio::spawn(tokio_ctrl_c(shutdown_send.clone()));
    let handle = tokio::spawn(async move {
        // Do some async work

        main_rusb(&mut shutdown_recv);

        "return value"
    });
    Ok(())
}

fn main_rusb(shutdown_recv: &mut UnboundedReceiver<()>) {
    loop {
        eprintln!("main_rusb");
        std::thread::sleep(std::time::Duration::from_secs(2));
        if let Ok(_) = shutdown_recv.try_recv() {
            break;
        }
    }
}

Unfortunately if it is not run from main thread this behaves in a way that Ctrl+C doesn't get triggered. Could somebody explain why and how to fix it?
Thanks

[alice]

When you returned from main, the shutdown process immediately started, and the runtime attempted to kill all tasks. It succeeded in killing the tokio_ctrl_c task, but since your other task is blocking the thread, it can't be killed.

To fix this:

1. Stop blocking the thread. Read this article to see how.
2. Make sure that you don't return from main until you want to exit the program.

[arnie]

@alice

but since your other task i

Thanks, I suspected that.
Best regards