Function crossterm::event::poll

pub fn poll(timeout: Duration) -> Result<bool>

Checks if there is an Event available.

Returns Ok(true) if an Event is available otherwise it returns Ok(false).

Ok(true) guarantees that subsequent call to the read function won’t block.

Arguments

• timeout - maximum waiting time for event availability

Examples

Return immediately:

use std::{time::Duration, io};
use crossterm::{event::poll};

fn is_event_available() -> io::Result<bool> {
    // Zero duration says that the `poll` function must return immediately
    // with an `Event` availability information
    poll(Duration::from_secs(0))
}

Wait up to 100ms:

use std::{time::Duration, io};

use crossterm::event::poll;

fn is_event_available() -> io::Result<bool> {
    // Wait for an `Event` availability for 100ms. It returns immediately
    // if an `Event` is/becomes available.
    poll(Duration::from_millis(100))
}