$re = '/-+(?:[0-9]*)-+\n(.*)\n((?:ERROR.*\n)*)real\s*(.*)\n.*\n.*\n\s*(.*)\s\s.*\n?/m';
$str = '-----------1------------
path/to/file1
real 0.21
user 0.01
sys 0.02
11378688 maximum resident set size
-----------2------------
path/to/file2
real 0.21
user 0.01
sys 0.02
11378688 maximum resident set size
-----------3------------
path/to/file3
real 0.21
user 0.01
sys 0.02
11378688 maximum resident set size
-----------4------------
path/to/file4
ERROR: Lorem ipsum error
ERROR2: Lorem ipsum error 2
real 0.59
user 0.01
sys 0.02
11378688 maximum resident set size';
preg_match_all($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