Matching

gistfile1.aw

<?php
$string = '/index/hi
/user/dfhds
/register/ddd
/etc/blah
/etc/';

preg_match_all("/^\/(?!(user|index|register))\w+\/\w*$/m", $string, $matches);

print_r($matches);

//Array
//(
//    [0] => Array
//        (
//            [0] => /etc/blah
//            [1] => /etc/
//        )
//
//    [1] => Array
//        (
//            [0] => 
//        )
//
//)