BUG: locks not working as expected

Description

The following code:

<?php
$arquivo_lock = fopen("test.txt","a");

if (flock($arquivo_lock,LOCK_EX|LOCK_NB)) { 
    echo "Yes";
} else {
    echo "No";
}

sleep(10);

fclose($arquivo_lock);
?>

Save the simple code above to the file test.php, for example. Now, in less than 10 seconds apart, open 2 (or more) tabs on your browser calling the file test.php and you will see every tab will show you Yes after some seconds. It should show Yes only on the first tab, all the other should return immediatly with No because I am using LOCK_NB flag.

This bug is pretty simple to reproduce and other people also confirmed it on Stackoverflow when I reported there.

PHP Version

8.x

Operating System

Confirmed at least on centos 9 stream and windows 11

まず、報告された CentOS 9 Stream と Windows 11 の環境で、PHP 8.x を使用して test.php の 2 タブによる再現を実行し、LOCK_EX|LOCK_NB を指定した flock に焦点を当てます。flock のエントリポイントとプラットフォーム固有のロック動作を追跡します。完了の条件は、最初のリクエストが Yes を報告し、重複するリクエストが直ちに No を返すことを、確認済みの環境でカバーできることです。