Ping ALL the machines in a subnet

playground.rs

use std::collections::BTreeMap;
use std::net::Ipv4Addr;
use std::thread;
use std::process::{Command, Stdio};

fn main() {
    let subnet: u8 = std::env::args()
        .skip(1)
        .next()
        .unwrap_or("20".into())
        .parse()
        .expect("failed to parse to byte");

    let check_hosts: Vec<_> = (1..255)
        .map(|i| {
            let ip = Ipv4Addr::new(192, 168, subnet, i);
            let worker = thread::spawn(move || {
                Command::new("ping")
                    .args(&["-c", "1", "-t", "2", &format!("{}", &ip)])
                    .stdout(Stdio::null())
                    .spawn()
                    .expect("failed to execute child")
                    .wait()
                    .expect("failed to wait on child")
                    .success()
            });

            (ip, worker)
        })
        .collect();

    let available_hosts: BTreeMap<Ipv4Addr, bool> = check_hosts.into_iter()
        .map(|(ip, worker)| {
            let exists = worker.join().expect("failed to get worker result");
            (ip, exists)
        })
        .collect();

    println!("{:#?}", available_hosts);
}