chan-and-fork.rs

#[macro_use]
extern crate chan;
extern crate chan_signal;
extern crate libc;

use chan_signal::Signal;
use std::thread;
use libc::fork;

fn main() {
    // Signal gets a value when the OS sent a INT or TERM signal.
    let signal = chan_signal::notify(&[Signal::INT, Signal::TERM]);
    // When our work is complete, send a sentinel value on `sdone`.
    let (sdone, rdone) = chan::sync(0);

    match unsafe { fork() } {
        0 =>  {
            run(sdone);
        },
        _ => {
            // Wait for a signal or for work to be done.
            chan_select! {
                signal.recv() -> signal => {
                    println!("received signal: {:?}", signal)
                },
                rdone.recv() => {
                    println!("Program completed normally.");
                }
            }
        }
    }
}

fn run(_sdone: chan::Sender<()>) {
    println!("Running work for 5 seconds.");
    println!("Can you send a signal quickly enough?");
    // Do some work.
    thread::sleep_ms(5000);

    // _sdone gets dropped which closes the channel and causes `rdone`
    // to unblock.
}