<?php $str = '123=one; two;45=three=four;6=five;'; ?>
Standard input is empty
Array ( [0] => Array ( [0] => 123=one; two; [1] => 45=three=four; [2] => 6=five; ) [1] => Array ( [0] => 123 [1] => 45 [2] => 6 ) [2] => Array ( [0] => one; two [1] => three=four [2] => five ) )