Crate polling

source ·
Expand description

Portable interface to epoll, kqueue, event ports, and wepoll.

Supported platforms:

  • epoll: Linux, Android
  • kqueue: macOS, iOS, FreeBSD, NetBSD, OpenBSD, DragonFly BSD
  • event ports: illumos, Solaris
  • poll: VxWorks, Fuchsia, other Unix systems
  • wepoll: Windows, Wine (version 7.13+)

Polling is done in oneshot mode, which means interest in I/O events needs to be re-enabled after an event is delivered if we’re interested in the next event of the same kind.

Only one thread can be waiting for I/O events at a time.

Examples

use polling::{Event, Poller};
use std::net::TcpListener;

// Create a TCP listener.
let socket = TcpListener::bind("127.0.0.1:8000")?;
socket.set_nonblocking(true)?;
let key = 7; // Arbitrary key identifying the socket.

// Create a poller and register interest in readability on the socket.
let poller = Poller::new()?;
poller.add(&socket, Event::readable(key))?;

// The event loop.
let mut events = Vec::new();
loop {
    // Wait for at least one I/O event.
    events.clear();
    poller.wait(&mut events, None)?;

    for ev in &events {
        if ev.key == key {
            // Perform a non-blocking accept operation.
            socket.accept()?;
            // Set interest in the next readability event.
            poller.modify(&socket, Event::readable(key))?;
        }
    }
}

Structs

  • Event
    Indicates that a file descriptor or socket can read or write without blocking.
  • Poller
    Waits for I/O events.

Traits