[php-src] Issue #12390: ```fgets``` memory usage

Issue: https://github.com/php/php-src/issues/12390 Author: AurelienPillevesse ### Description The following code: ```php <?php $stream = fopen($filename, 'r'); if ($stream === false) { throw new \Exception('Failed to open file: ' . $filename); } $list = []; while (($line = fgets($stream)) !== false) { if (preg_match($beginningPattern, $line, $matches)) { $tmp = $line; while (($line = fgets($stream)) !== false) { $tmp .= $line; if (preg_match($endingPattern, $line)) { $list[] = $tmp; break; } } } } ``` The downloaded file used is the script is this one : https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008.pdf Resulted in this output: ``` string(29) "Memory usage: 31.68 MB bytes" string(34) "Peak memory usage: 36.87 MB bytes" ``` It seems that it takes a lot of memory resource to iterate over the file and I can see this in the function : https://github.com/php/php-src/blob/master/ext/standard/file.c#L912 Maybe an improvement is possible with this TODO or something else ? ### PHP Version 8.1 ### Operating System Windows