use tokio::{sync::oneshot, time::{sleep, Duration}};async fn check_for_one() {// This loop will continuously print "write" every second until interruptedloop {println!("write");sleep(Duration::from_secs(1)).await; // Non-blocking sleep in async context}
}#[tokio::main]
async fn main() {// Create a oneshot channellet (tx1, rx1) = oneshot::channel::<&str>();// Spawn a task that sends a message after 2 secondstokio::spawn(async move {sleep(Duration::from_secs(2)).await; let _ = tx1.send("one");});// Use tokio::select! to wait for either the print task or the message on rx1tokio::select! {_ = check_for_one() => {// This branch will continuously print "write" every secondprintln!("check_for_one completed");}val = rx1 => {// This branch will be executed once the message is received from rx1match val {Ok(val) => println!("rx1 completed first with {:?}", val),Err(e) => println!("Failed to receive from rx1: {:?}", e),}}}println!("main thread exiting");
}
只要有一个异步任务完成，就会退出select！ 。
