$file_download = "1__".md5('1').".html";
    $url = "http://www.site.com.br/".$file_download.";

    $arquivo = $url ;
    $handle = @fopen($arquivo, "rb");
    $cont = @fread($handle, 100);

    if($cont == "verifica-licenca") {
        echo 1;
    } else {
        echo 0;
    }