Loop over WordPress MU (aka Network) sites, calling a script on each via HTTP

wpmu-loop.php

<?php

/* example use: http://example.com/wpmu-loop.php?script=wp-fixup-tags.php */
/* see also: https://gist.github.com/1645313 */

define('WP_INSTALLING', true);
require_once('wp-load.php');

/* get_blogs() only knows about sub-domain blogs, not sub-directory blogs
  it's probably just a case of appending the path column to the result    */
function get_blogs() {
  global $wpdb;

  $query = "SELECT domain from wp_blogs";
  $blogs = $wpdb->get_results($query, ARRAY_N);

  return($blogs);
}


$blogs = get_blogs();

print "<pre>\n";
if ($blogs) {
  print "blogs: "  . count($blogs) . "\n";

  foreach ($blogs as $blog) {
    print $blog[0] . "\n";
    ob_flush();
    if (!empty($_GET['script'])) {
      print file_get_contents("http://" . $blog[0] . "/" . $_GET['script']);
      print "\n";
      ob_flush();
    }
  }
}
print "</pre>";
?>