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Function std::env::var

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

Fetches the environment variable key from the current process.

Errors

  • Environment variable is not present
  • Environment variable is not valid unicode

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