$re = '/\/.*(?=\\\\)/m';
$str = '8670 b\'/home/giampaolo/Nextcloud/KJ/risorse varie/ricerche/pdf/Screenshot_20181203_163257.xcf\\n\'
8671 b\'/home/giampaolo/Nextcloud/KJ/risorse varie/20181122_120359-Kickstarter-online.png\\n\'
8672 b\'/home/giampaolo/Nextcloud/Komatsu.mp4\\n\'
8673 b\'/home/giampaolo/20190609rsync_HM-1_4T\\n\'
8674 b\'/home/giampaolo/Prada-1913_HK.ods\\n\'
8675 b\'/home/giampaolo/2019 09 12 Registrazione EPO.pdf\\n\'
8676 b\'/home/giampaolo/20190915-list_of_kernels\\n\'
8677 b\'/home/giampaolo/20190916-installed_packages\\n\'
8678 b\'/home/giampaolo/find_3_days\\n\'';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php