use std::env::var; fn main() { if var("CARGO_FEATURE_LOGIND").ok().is_none() { println!("cargo:warning=You are compiling anvil without logind support."); println!("cargo:warning=This means that you'll likely need to run it as root if you want to launch it from a tty."); println!("cargo:warning=To enable logind support add `--feature logind` to your cargo invocation:"); println!("cargo:warning=$ cd anvil; cargo run --feature logind"); } }