组件ThreadChannel::capacity()

ThreadChannel::capacity ​

(PHP 8.6+, True Async 1.0)

php
public ThreadChannel::capacity(): int

返回构造时设置的通道容量。

  • 0 — 无缓冲（同步）通道：send() 阻塞直到接收方准备好。
  • 正数 — 缓冲区可同时容纳的最大值数量。

容量在通道的整个生命周期内固定不变。

返回值 ​

通道缓冲区容量（int）。

示例 ​

示例 #1 检查容量 ​

php
<?php

use Async\ThreadChannel;

$unbuffered = new ThreadChannel();
echo $unbuffered->capacity(); // 0

$buffered = new ThreadChannel(64);
echo $buffered->capacity(); // 64

示例 #2 基于通道类型的自适应逻辑 ​

php
<?php

use Async\ThreadChannel;

function describeChannel(ThreadChannel $ch): void {
    if ($ch->capacity() === 0) {
        echo "Unbuffered: each send() blocks until recv() is called\n";
    } else {
        $free = $ch->capacity() - $ch->count();
        echo "Buffered: capacity {$ch->capacity()}, {$free} slot(s) free\n";
    }
}

$ch = new ThreadChannel(8);
$ch->send('item');
describeChannel($ch); // "Buffered: capacity 8, 7 slot(s) free"

参见 ​