How can I find when a folders content was last modified efficiently in php

Question

I need to run a check on a folder to see when it was last modified. By this I mean the last time it, or any of the files it contains where last modified.

I have tried two ways so far:

using the stat() function on the folder, and then grabbing mtime
```
$stat = stat("directory/path/");
echo $stat["mtime"];
```
using the filemtime() function on the folder
```
echo (filemtime("directory/path/"));
```

Both of these methods return the same value, and this value does not change if I update one of the files. I am guessing this is because the folder structure itself does not change, only the content of one of the files.

I guess I could loop through all the files in the directory and check their modification dates, but there are potentially a lot of files and this doesn't seem very efficient.

Can anyone suggest how I might go about getting a last modification time for a folder and its content in an efficient way?

Maybe take a look at the SplFileInfo class: http://www.php.net/manual/en/class.splfileinfo.php — Dirk McQuickly, Dec 14 '13 at 17:42
@DirkMcQuickly Using SplFileInfo getMTime() gives me exactly the same result as stat and filemtime — Finglish, Dec 14 '13 at 17:53
If you need to check on a regular basis, you could keep track of the last file change in a text file (when you change a file, change the text file), and get your value from there. — Dirk McQuickly, Dec 14 '13 at 18:10
@DirkMcQuickly I thought about this, but in this case, the files maybe edited in php or uploaded by a third party. If they are uploaded directly to the system the text file wont be updated. — Finglish, Dec 14 '13 at 18:17

score 2 · Answer 1 · edited May 23 '17 at 12:31

2

moi.

I suggest that you loop all files using foreach function and use it, i think there's no function for that purpose. Here's very simple example using that loop:

$directory = glob('gfd/*');
foreach ($directory as $file) {
    $mdtime = date('d.m.Y H:i:s', filemtime($file));
}
echo "Folder last modified: $mdtime<br />";

Keep in mind that foreach is pretty fast, and if you have files < 3000, i think there's nothing to worried about. If you don't want to use this, you can always save modification date to file or something like that. :)

Subfolder-compatibility:

function rglob($pattern, $flags = 0) {
    $files = glob($pattern, $flags); 
     foreach (glob(dirname($pattern).'/*', GLOB_ONLYDIR|GLOB_NOSORT) as $dir) {
         $files = array_merge($files, rglob($dir.'/'.basename($pattern), $flags));
     }
     return $files;
}

See this question: php glob - scan in subfolders for a file

edited May 23 '17 at 12:31

Community

1
1

answered Dec 14 '13 at 18:28

aksu

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You're not taking sub folders in consideration, though. Make this recursive and I'll +1 you. – h2ooooooo Dec 14 '13 at 18:31
Thanks. My main concern is speed an efficiency as this is likely to get a lot of use. I had not thought of using glob(). – Finglish Dec 14 '13 at 18:40
@h2ooooooo Here you go. ;) – aksu Dec 14 '13 at 18:49
1

In that case, you can also use the RecursiveDiretoryIterator. http://www.php.net/manual/en/class.recursivedirectoryiterator.php – Dirk McQuickly Dec 14 '13 at 19:24
@Finglish glob() is no faster than any other method of looping through all the files. So, this answer adds nothing new to what you stated your question. foreach is indeed fast but is is not foreach which is a bottleneck in this scenario. – Your Common Sense Dec 15 '13 at 17:33

How can I find when a folders content was last modified efficiently in php

1 Answers1