--TEST-- XORing strings --FILE-- <?php $s = "123"; $s1 = "234"; var_dump(bin2hex($s ^ $s1)); $s = "1235"; $s1 = "234"; var_dump(bin2hex($s ^ $s1)); $s = "some"; $s1 = "test"; var_dump(bin2hex($s ^ $s1)); $s = "some long"; $s1 = "test"; var_dump(bin2hex($s ^ $s1)); $s = "some"; $s1 = "test long"; var_dump(bin2hex($s ^ $s1)); $s = "some"; $s ^= "test long"; var_dump(bin2hex($s)); echo "Done\n"; ?> --EXPECTF-- string(6) "030107" string(6) "030107" string(8) "070a1e11" string(8) "070a1e11" string(8) "070a1e11" string(8) "070a1e11" Done