<?
$arq = "contador.txt";

$abre = fopen($arq, "r");
$total = fread($abre, filesize($arq));
fclose($abre);

$abre = fopen($arq, "w");
$total = $total + 1;
$salva = fwrite($abre, $total);
fclose($abre);

echo $total;
?>