我如何修改readdir（）列出文件的方式。

Question

I have a script that creates a zip package daily in a directory. After this is done another script deletes the 'last' file in the directory so I always have just the latest x days.

while (false !== ($file = readdir($handle))) 
    {
            if ($file != "." && $file != "..")
            {
                echo "$file";
                echo '<br>';

                //count files
                $file_count = $file_count + 1;
            }
        }

However suddenly readdir() is returning the list of files like this:

March_16_2011.zip

March_12_2011.zip

March_13_2011.zip

March_14_2011.zip

March_15_2011.zip

So of course rather than the oldest file being removed the newest one is.

When I look at the files in FTP they are all dated correctly.

Why is readdir() returning them out of order in this case? How do I force it to order them in a way I want? (By date)

Answer 1

readdir returns the filenames in an arbitrary order, depending on how the OS returns the entries from the filesystem. You need to manually sort the result list:

foreach (glob("*") as $fn) {
    $files[$fn] = filemtime($fn);
}
arsort($files);
$files = array_keys($files);