Struct Event 

pub struct Event {
    pub key: usize,
    pub readable: bool,
    pub writable: bool,
    /* private fields */
}

Indicates that a file descriptor or socket can read or write without blocking.

Fields

key: usize

Key identifying the file descriptor or socket.

readable: bool

Can it do a read operation without blocking?

writable: bool

Can it do a write operation without blocking?

Implementations

impl Event

pub const fn new(key: usize, readable: bool, writable: bool) -> Event

Create a new event.

pub const fn all(key: usize) -> Event

All kinds of events (readable and writable).

Equivalent to: Event::new(key, true, true)

pub const fn readable(key: usize) -> Event

Only the readable event.

Equivalent to: Event::new(key, true, false)

pub const fn writable(key: usize) -> Event

Only the writable event.

Equivalent to: Event::new(key, false, true)

pub const fn none(key: usize) -> Event

No events.

Equivalent to: Event::new(key, false, false)

pub fn set_interrupt(&mut self, active: bool)

Add interruption events to this interest.

This usually indicates that the file descriptor or socket has been closed. It corresponds to the EPOLLHUP and POLLHUP events.

Interruption events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this function is a no-op.

pub fn set_rd_interrupt(&mut self, active: bool)

Add rd interruption events to this interest.

This usually indicates that the file descriptor or socket has been closed. It corresponds to the EPOLLRDHUP and POLLRDHUP events.

Interruption events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this function is a no-op.

pub fn with_interrupt(self) -> Event

Add interruption events to this interest.

This usually indicates that the file descriptor or socket has been closed. It corresponds to the EPOLLHUP and POLLHUP events.

Interruption events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this function is a no-op.

pub fn with_rd_interrupt(self) -> Event

Add rd interruption events to this interest.

This usually indicates that the file descriptor or socket has been closed. It corresponds to the EPOLLRDHUP and POLLRDHUP events.

Interruption events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this function is a no-op.

pub fn set_priority(&mut self, active: bool)

Add priority events to this interest.

This indicates that there is urgent data to read. It corresponds to the EPOLLPRI and POLLPRI events.

Priority events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this function is a no-op.

pub fn with_priority(self) -> Event

Add priority events to this interest.

This indicates that there is urgent data to read. It corresponds to the EPOLLPRI and POLLPRI events.

Priority events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this function is a no-op.

pub fn is_interrupt(&self) -> bool

Tell if this event is the result of an interrupt notification.

This usually indicates that the file descriptor or socket has been closed. It corresponds to the EPOLLHUP and POLLHUP events.

Interruption events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this always returns false.

pub fn is_rd_interrupt(&self) -> bool

Tell if this event is the result of an rd interrupt notification.

pub fn is_priority(&self) -> bool

Tell if this event is the result of a priority notification.

This indicates that there is urgent data to read. It corresponds to the EPOLLPRI and POLLPRI events.

Priority events are only supported on the following platforms:

• epoll
• poll
• IOCP
• Event Ports

On other platforms, this always returns false.

pub fn is_connect_failed(&self) -> Option<bool>

👎Deprecated since 3.4.0:

use is_err in combination of is_hup instead, see documentation for is_err

Tells if this event is the result of a connection failure.

This function checks if a TCP connection has failed. It corresponds to the EPOLLERR or EPOLLHUP event in Linux and CONNECT_FAILED event in Windows IOCP.

Examples

use std::{io, net};
// Assuming polling and socket2 are included as dependencies in Cargo.toml
use polling::Event;
use socket2::Type;

fn main() -> io::Result<()> {
    let socket = socket2::Socket::new(socket2::Domain::IPV4, Type::STREAM, None)?;
    let poller = polling::Poller::new()?;
    unsafe {
        poller.add(&socket, Event::new(0, true, true))?;
    }
    let addr = net::SocketAddr::new(net::Ipv4Addr::LOCALHOST.into(), 8080);
    socket.set_nonblocking(true)?;
    let _ = socket.connect(&addr.into());

    let mut events = polling::Events::new();

    events.clear();
    poller.wait(&mut events, None)?;

    let event = events.iter().next();

    let event = match event {
        Some(event) => event,
        None => {
            println!("no event");
            return Ok(());
        },
    };

    println!("event: {:?}", event);
    if event
        .is_connect_failed()
        .unwrap_or_default()
    {
        println!("connect failed");
    }

    Ok(())
}

Returns

Returns Some(true) if the connection has failed, Some(false) if the connection has not failed, or None if the platform does not support detecting this condition.

pub fn is_err(&self) -> Option<bool>

Tells if this event is the result of a connection failure.

This function checks if an error exist, particularly useful in detecting if TCP connection failed. It corresponds to the EPOLLERR event in Linux and CONNECT_FAILED event in Windows IOCP.

Caveats

In epoll, a TCP connection failure is indicated by EPOLLERR + EPOLLHUP, though just EPOLLERR is enough to indicate a connection failure. EPOLLHUP may happen when we haven’t event called connect on the socket, but it is still a valid event to check for.

Returns Some(true) if the connection has failed, Some(false) if there is no error, or None if the platform does not support detecting this condition.

pub fn clear_extra(&mut self)

Remove any extra information from this event.

pub fn with_no_extra(self) -> Event

Get a version of this event with no extra information.

This is useful for comparing events with ==.

Trait Implementations

impl Clone for Event

fn clone(&self) -> Event

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Event

impl Debug for Event

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Eq for Event

impl PartialEq for Event

fn eq(&self, other: &Event) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Event