php - ob_start / fputs suddenly doesn't work anymore, is there anything that can stop it?

My code:

function log_this($to_log, $prepend = null){

    ob_start();
    $fn = '../info.log';        
    $fp = fopen($fn, 'a');

    fputs($fp, "\r\rnew log -------- \r\r");

    if(isset($prepend)) fputs($fp, $prepend . ":\r\r");

    var_dump($to_log);
    $content = ob_get_contents();

    fputs($fp, $content);
    fclose($fp);
    ob_end_clean();
}

It's a function I always use in my local environment (MAMP) to log things from wordpress. it always worked. Now it doesn't work anymore. I tried to understand why for a couple of days but can't find any solution. I'm not a really advanced php programmer, so maybe there's something I don't know and should.. Can anyone help me please?

By the way, function_exists and also file_exists, from where I call it.

I'm not sure why fputs isn't working, it is probably to do with your servers folder permissions (usually 0755 or 0775 is safe), could also add a condition to check is_writable to eliminate that possibility. Have you tried using file_get_contents and file_put_contents.

define('FILE_PATH', 'path/to/file/file.log'); 
    function log_this($command, $array = null) {
    //check if we can get to the file
    if(file_exists(FILE_PATH)){
    $current = file_get_contents(FILE_PATH);
    $current .= $command;
    if(!is_null($array)){
    ob_start();print_r($array);$output = ob_get_clean();
    $current .= $output;
    }
    file_put_contents(FILE_PATH, $current);
    }
 }