Python web frameworks. It is not based on WSGI, and it is typically run with only one thread per process. See the User’s guide for more on Tornado’s approach to asynchronous programming. While some support supported or recommended for pro- duction use. Some features are missing on Windows (including multi-process mode) and scalability is limited (Even though Tornado is built on asyncio, which supports Windows Configure your operating system or process manager to run this program to start the server. Please note that it may be necessary to increase the number of open files per process (to avoid “Too many open files”-Error)

WSGI [https://wsgi.readthedocs.io/en/latest/], and it is typically run with only one thread per process. See the User’s guide for more on Tornado’s approach to asynchronous programming. While some support supported or recommended for production use. Some features are missing on Windows (including multi-process mode) and scalability is limited (Even though Tornado is built on asyncio, which supports Windows coroutines tornado.locks – Synchronization primitives tornado.queues – Queues for coroutines tornado.process — Utilities for multiple processes Integration with other services tornado.auth — Third-party login

值则会以非零值退出；成功退出的程序会返回整数 0，运行错误的程序会返回 非 0 的整数。Rust 也会从二进制程序中返回与这个惯例相兼容的整数。 main 函数也可以返回任何实现了 std::process::Termination trait 的类型，它包含了一个返 回 ExitCode 的 report 函数。请查阅标准库文档了解更多为自定义类型实现 Termination trait 的细节。 panic! 负责的工作， 即以非零错误码退出命令行工具的工作。非零的退出状态是一个惯例信号，用来告诉调用程序 的进程：该程序以错误状态退出了。 文件名：src/main.rs use std::process; fn main() { let args: Vec = env::args().collect(); let config = Config::build(&args) Config::build(&args).unwrap_or_else(|err| { println!("Problem parsing arguments: {err}"); process::exit(1); }); // --snip-- 示例 12-10：如果新建 Config 失败则使用错误码退出 在上面的示例中，使用了一个之前没有详细说明的方法：unwrap_or_else，它定义于标准库的