I need to create a function that lists subfolders of a given folder, that contain at least one .txt file. I found the following function, which displays a list of file that match a pattern in a directory tree: function find($dir, $pattern){ $dir = escapeshellcmd($dir); $files = glob("$dir/$pattern"); foreach (glob("$dir/{.[^.]*,*}", GLOB_BRACE|GLOB_ONLYDIR) as $sub_dir) //look in subdirectories { $arr = find($sub_dir, $pattern); //recursive call $files = array_merge($files, $arr); // merge array with files from subdirectory } return $files; } $txtFiles=find("project/sys","*.txt"); foreach ($txtFiles as $txtFile) { echo '<h2>'.$txtFile.'</h2>'; //display all text files } PHP: My question is, how do I change the function to return only folders that contain at least one text file. But, the functions should look inside child folders of "project/sys" and list a child folder only once if that folder or any of its child folders contain at least one text file. I'll give an example of the output I'm looking for: Folder list project/sys/diagram project/sys/bin project/sys/scripts project/sys/styles project/sys/meta The above folders may not contain a text file directly, but their children folders do. However, I'm not interested in their children folder and I want to list the above level folder only once for each folder. Thanks in advance