Rust JoinHandle用法及代碼示例

本文簡要介紹rust語言中 Struct std::thread::JoinHandle 的用法。

用法

pub struct JoinHandle<T>(_);

加入線程的擁有權限(在其終止時阻塞)。

A JoinHandle 分離關聯的線程被刪除時，這意味著不再有任何線程句柄，也沒有辦法join在上麵。

由於平台限製，無法 Clone 這個句柄：加入線程的能力是 uniquely-owned 權限。

此struct 由 thread::spawn 函數和 thread::Builder::spawn 方法創建。

例子

從 thread::spawn 創建：

use std::thread;

let join_handle: thread::JoinHandle<_> = thread::spawn(|| {
    // some work here
});

從 thread::Builder::spawn 創建：

use std::thread;

let builder = thread::Builder::new();

let join_handle: thread::JoinHandle<_> = builder.spawn(|| {
    // some work here
}).unwrap();

一個線程被分離並超過了產生它的線程：

use std::thread;
use std::time::Duration;

let original_thread = thread::spawn(|| {
    let _detached_thread = thread::spawn(|| {
        // Here we sleep to make sure that the first thread returns before.
        thread::sleep(Duration::from_millis(10));
        // This will be called, even though the JoinHandle is dropped.
        println!("♫ Still alive ♫");
    });
});

original_thread.join().expect("The thread being joined has panicked");
println!("Original thread is joined.");

// We make sure that the new thread has time to run, before the main
// thread returns.

thread::sleep(Duration::from_millis(1000));

相關用法

注：本文由純淨天空篩選整理自rust-lang.org大神的英文原創作品 Struct std::thread::JoinHandle。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。