Channel::isClosed

(PHP 8.6+, True Async 1.0)

public Channel::isClosed(): bool

Checks whether the channel has been closed by a close() call.

A closed channel does not accept new values via send(), but allows reading remaining values from the buffer via recv().

Return values

true — the channel is closed. false — the channel is open.

Examples

Example #1 Checking channel state

<?php

use Async\Channel;

$channel = new Channel(5);

echo $channel->isClosed() ? "closed" : "open"; // "open"

$channel->send('data');
$channel->close();

echo $channel->isClosed() ? "closed" : "open"; // "closed"

// You can still read the buffer even after closing
$value = $channel->recv(); // "data"

Example #2 Conditional sending

<?php

use Async\Channel;

$channel = new Channel(10);

spawn(function() use ($channel) {
    while (!$channel->isClosed()) {
        $data = produceData();
        $channel->send($data);
        delay(100);
    }
    echo "Channel closed, stopping sends\n";
});

See also

Channel::close — Close the channel
Channel::isEmpty — Check if the buffer is empty