PHP Cookbook

19.9. Processing All Files in a Directory

Problem

You want to do something to all the files in a directory and in any subdirectories.

Solution

Use the pc_process_dir( ) function, shown in Example 19-1, which returns a list of all files in and beneath a given directory.

Example 19-1. pc_process_dir( )

function pc_process_dir($dir_name,$max_depth = 10,$depth = 0) {
    if ($depth >= $max_depth) {
        error_log("Reached max depth $max_depth in $dir_name.");
        return false;
    }
    $subdirectories = array();
    $files = array();
    if (is_dir($dir_name) && is_readable($dir_name)) {
        $d = dir($dir_name);
        while (false !== ($f = $d->read())) {
            // skip . and .. 
            if (('.' == $f) || ('..' == $f)) {
                continue;
            }
            if (is_dir("$dir_name/$f")) {
                array_push($subdirectories,"$dir_name/$f");
            } else {
                array_push($files,"$dir_name/$f");
            }
        }
        $d->close();
        foreach ($subdirectories as $subdirectory) {
            $files = array_merge($files,pc_process_dir($subdirectory,$max_depth,$depth+1));
        }
    } 
    return $files;
}

Discussion

Here’s an example: if /tmp contains the files a and b, as well as the directory c, and /tmp/c contains files d and e, pc_process_dir('/tmp') returns an array with elements /tmp/a, /tmp/b, /tmp/c/d, and /tmp/c/e. To perform an operation on each file, iterate through the array:

$files = pc_process_dir('/tmp');
foreach ($files as $file) {
  print "$file was last accessed at ".strftime('%c',fileatime($file))."\n";
}

Instead of returning an array of files, you can also write a function that processes them as it finds them. The ...