Create / Edit a file on the server (Apache)

With the following code I would like to create a file on the server.

<?php
    date_default_timezone_set('America/Sao_Paulo');
    $nomeArquivoLogDia = date('Ymd') . '-teste.log';

    if (file_exists($nomeArquivoLogDia)) {
        $arquivoLog = file($nomeArquivoLogDia, FILE_SKIP_EMPTY_LINES);    
    } else {
        $arquivoLog = fopen($nomeArquivoLogDia, "w+");
    }
?>

When I run php ( link ) the file is not generated.

Does anyone know how to do this?