- printf: documentation ( source)
<?php
$xs = array(3, 4, 5, 7);
$xs2 = new ArrayObject($xs);
$it = $xs2->getIterator();
$it->rewind();
printf("%d\n", $it->current());
$it->next();
printf("%d\n", $it->current());
$it->next();
printf("%d\n", $it->current());