std::env::var

Function std::env::var

pub fn var<K: AsRef<OsStr>>(key: K) -> Result<String, VarError>

Fetches the environment variable key from the current process.

The returned result is Ok(s) if the environment variable is present and is valid unicode. If the environment variable is not present, or it is not valid unicode, then Err will be returned.

Examples

use std::env;

let key = "HOME";
match env::var(key) {
    Ok(val) => println!("{}: {:?}", key, val),
    Err(e) => println!("couldn't interpret {}: {}", key, e),
}

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/env/fn.var.html

在线笔记
App下载
App下载

扫描二维码

下载编程狮App

公众号
微信公众号

编程狮公众号

意见反馈
返回顶部