$re = '/".*?" [0-9]{3}/';
$str = '[16/Aug/2016:06:13:25 -0400] "GET /file/ HTTP/1.1" 302 random stuff ignore
[16/Aug/2016:06:13:25 -0400] "" 400 random stuff ignore';
preg_match_all($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