$re = '@/((\w+)\.)?(\w+)\.(\w{3})$@m';
$str = 'c:/my_project/sources/hr.manage_employees.pks
c:/my_project/sources/hr.manage_employees.pkb
c:/my_project/sources/hr.employee_typ.tps
c:/my_project/sources/hr.employee_typ.tpb
c:/my_project/sources/hotel.manage_rooms.pks
c:/my_project/sources/hotel.manage_rooms.pkb
c:/my_project/tests/hr.test_manage_employees.pks
c:/my_project/tests/hr.test_manage_employees.pkb
c:/my_project/tests/hotel.test_manage_rooms.pks
c:/my_project/tests/hotel.test_manage_rooms.pkb';
preg_match_all($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