PHP: How to check if file not exists or permission is denied?

Question

I want to check if file do not exists. When file_exists() function returns false I can\'t be sure if the file do not exist or I don\'t have permiss

Answer 1

I wrote function which check if file can exists. It return false if there is no such file in filesystem, otherwise it returns true. My function checks (bottom-up) directory structure. One should be fairly sure that $root directory exists.

private function fileCanExists($root, $path) {
    $root .= '/';
    if (file_exists($root . $path))
        return true;
    while ($path != '.') {
        $path = dirname($path);
        if (file_exists($root . $path)) {
            if (is_readable($root . $path))
                return false;
            else
                return true;
        }
    }
    return false;
}

That is what mean when I wrote:

I want to check if file do not exists.