3v4l.org

run code in 200+ php & hhvm versions
<?php $row = ['a\\"', 'bbb']; $fp = fopen('php://memory', 'w+'); fputcsv($fp, $row); rewind($fp); echo stream_get_contents($fp); fclose($fp);
based on AXrGQ
Output for 5.6.0 - 5.6.30, hhvm-3.18.4 - 3.21.0, 7.0.0 - 7.3.1
"a\"",bbb