delay()

delay() — suspend a coroutine for a given number of milliseconds.

delay ​

(PHP 8.6+, True Async 1.0)

delay() — Suspends execution of the current coroutine for the specified number of milliseconds.

Description ​

php
delay(int $ms): void

Suspends the coroutine, yielding control to the scheduler. After $ms milliseconds, the coroutine will be resumed. Other coroutines continue to execute during the wait.

Parameters ​

ms Wait time in milliseconds. If 0, the coroutine simply yields control to the scheduler (similar to suspend(), but with queueing).

Return Values ​

No return value.

Examples ​

Example #1 Basic usage ​

php
<?php
use function Async\spawn;
use function Async\delay;

spawn(function() {
    echo "Start\n";
    delay(1000); // Wait 1 second
    echo "1 second passed\n";
});
?>

Example #2 Periodic execution ​

php
<?php
use function Async\spawn;
use function Async\delay;

spawn(function() {
    while (true) {
        echo "Checking status...\n";
        delay(5000); // Every 5 seconds
    }
});
?>

Notes ​

Note: delay() does not block the entire PHP process — only the current coroutine is blocked.

Note: delay() automatically starts the scheduler if it has not been started yet.

See Also ​