An event source that may be registered with Registry.

Types that implement event::Source can be registered with Registry. Users of Mio should not use the event::Source trait functions directly. Instead, the equivalent functions on Registry should be used.

See Registry for more details.

Implementing event::Source

Event sources are always backed by system handles, such as sockets or other system handles. These event::Sources will be monitored by the system selector. An implementation of Source will almost always delegates to a lower level handle. Examples of this are TcpStreams, or the unix only SourceFd.

Dropping event::Sources

All event::Sources, unless otherwise specified, need to be deregistered before being dropped for them to not leak resources. This goes against the normal drop behaviour of types in Rust which cleanup after themselves, e.g. a File will close itself. However since deregistering needs access to Registry this cannot be done while being dropped.

Examples

Implementing Source on a struct containing a socket:

use mio::{Interest, Registry, Token};
use mio::event::Source;
use mio::net::TcpStream;

use std::io;

# #[allow(dead_code)]
pub struct MySource {
    socket: TcpStream,
}

impl Source for MySource {
    fn register(&mut self, registry: &Registry, token: Token, interests: Interest)
        -> io::Result<()>
    {
        // Delegate the `register` call to `socket`
        self.socket.register(registry, token, interests)
    }

    fn reregister(&mut self, registry: &Registry, token: Token, interests: Interest)
        -> io::Result<()>
    {
        // Delegate the `reregister` call to `socket`
        self.socket.reregister(registry, token, interests)
    }

    fn deregister(&mut self, registry: &Registry) -> io::Result<()> {
        // Delegate the `deregister` call to `socket`
        self.socket.deregister(registry)
    }
}