<?

$step = 20;

$file = file('text.txt');

$total = count($file);

$page = isset($_GET['page']) ? abs(intval($_GET

['page'])) : 0;

if(($page+$step) > $total){

$next = $total;

}else{

$next = $page+$step;

}

for($i=$page; $i<$next; $i++){

echo $file[$i].'<br>';

}

?>