[PHP-NOTES] note 130545 added to function.fopen

i had to do such function to display newest log entries on top to be displayed in browser
its easy to adjust it from anonymous to normal function and/or add content on end
most important is same log can be used by many threads/processes (Swoole, ReactPHP, php_fpm)
also it had to keep reasonable size to load fast

$prependFileThreadSafe = static function (string $file, string $content, int $maxLen = 1024*500): void {
    $f = fopen($file, 'c+');
    flock($f, LOCK_EX);
    $prev = fread($f, $maxLen-strlen($content));
    fseek($f, 0);
    fwrite($f, $content . $prev);
    flock($f, LOCK_UN);
    fclose($f);
};

usage:
$prependFileThreadSafe('my.log', "some content\n");
----
Server IP: 45.112.84.4
Probable Submitter: 80.90.5.137 (proxied: 178.219.142.108)
----
Manual Page -- https://php.net/manual/en/function.fopen.php
Edit        -- https://main.php.net/note/edit/130545
Del: integrated  -- https://main.php.net/note/delete/130545/integrated
Del: useless     -- https://main.php.net/note/delete/130545/useless
Del: bad code    -- https://main.php.net/note/delete/130545/bad+code
Del: spam        -- https://main.php.net/note/delete/130545/spam
Del: non-english -- https://main.php.net/note/delete/130545/non-english
Del: in docs     -- https://main.php.net/note/delete/130545/in+docs
Del: other reasons-- https://main.php.net/note/delete/130545
Reject      -- https://main.php.net/note/reject/130545
Search      -- https://main.php.net/manage/user-notes.php