Function std::env::var_os
[−]
[src]
pub fn var_os<K: AsRef<OsStr>>(key: K) -> Option<OsString>
Fetches the environment variable key
from the current process, returning
None if the variable isn't set.
Examples
fn main() { use std::env; let key = "HOME"; match env::var_os(key) { Some(val) => println!("{}: {:?}", key, val), None => println!("{} is not defined in the environment.", key) } }use std::env; let key = "HOME"; match env::var_os(key) { Some(val) => println!("{}: {:?}", key, val), None => println!("{} is not defined in the environment.", key) }