并发

多线程

fn main() {
    print!("\n");
    let fn_thread = thread::spawn(|| loop {
        println!("你好！");
        thread::sleep(time::Duration::from_millis(100)); // sleep 0.1秒
    });

    fn_thread.join().unwrap(); // 阻塞主线程
}

消息传递

use std::{sync::mpsc, thread};

fn main() {
    let (tx, rx) = mpsc::channel();

    thread::spawn(move || {
        let val = String::from("hi");
        tx.send(val).unwrap();
    });

    let received = rx.recv().unwrap(); // 收到值前阻塞
    // try_recv() // 不会阻塞
    println!("Got: {}",received);
}

Got: hi

use std::{sync::mpsc, thread, time::Duration, vec};

fn main() {
    let (tx, rx) = mpsc::channel();

    thread::spawn(move || {
        let vals = vec![
            String::from("Hi"),
            String::from("from"),
            String::from("the"),
            String::from("thread"),
        ];
        for val in vals {
            tx.send(val).unwrap();
            thread::sleep(Duration::from_millis(1));
        }
    });

    for received in rx {
        println!("Got: {}", received);
    }
}

output

Got: Hi
Got: from
Got: the
Got: thread

共享内存

use std::sync::Mutex;

fn main() {
    let m = Mutex::new(5);

    {
        let mut num = m.lock().unwrap();
        *num = 6;
    }

    println!("m = {:?}", m);
}

m = Mutex { data: 6, poisoned: false, .. }

Mutex可能产生死锁

其他

可以使用Arc<\T>， 用法与Rc<\T>类似

使用Send 和 Sync trait拓展并发，但是手动实现Send 和 Sync是不安全的

Arc<\T>