3v4l.org

run code in 300+ PHP versions simultaneously
<?php $row = array(); $row[] = 'a\\"'; $row[] = 'bbb'; $fp = fopen('php://memory', 'w+'); fputcsv($fp, $row, ',', '"', '~'); rewind($fp); var_dump(stream_get_contents($fp)); fclose($fp);
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.26, 8.1.0 - 8.1.13
string(11) ""a\""",bbb "

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72.92 ms | 410 KiB | 5 Q