async-signal-with-info

Asynchronous signal handling.

This crate provides the Signals type, which can be used to listen for POSIX signals asynchronously. It can be seen as an asynchronous version of signal_hook::iterator::Signals.

This is a fork of async-signal to also provide siginfo_t via the async stream. As siginfo_t is a Unix specific feature, support for Windows is also removed from the crate.

Implementation

This crate uses the signal_hook_registry crate to register a listener for each signal. That listener will then send a message through a Unix socket to the Signals type, which will receive it and notify the user. Asynchronous notification is done through the futures-channel crate.

A background thread is used for reading signal messages to avoid signal losses caused by buffer overruns, which is a problem for the original crate.

Examples

use async_signal::{Signal, Signals};
use futures_lite::prelude::*;
use signal_hook::low_level;

// Register the signals we want to receive.
let mut signals = Signals::new([
    Signal::Term,
    Signal::Quit,
    Signal::Int,
])?;

// Wait for a signal to be received.
while let Some((signal, siginfo)) = signals.next().await {
    // Print the signal.
    eprintln!("Received signal {:?} {:p}", signal, unsafe { siginfo.si_value().sigval_ptr });

    // After printing it, do whatever the signal was supposed to do in the first place.
    low_level::emulate_default_handler(signal.unwrap() as i32).unwrap();
}

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.