Bulk checkDomainRequest
From Openprovider API documentation
Before using this script, please make sure to read API General Examples
<?php
require_once('API.php');
$api = new OP_API('https://api.openprovider.eu');
$username = '--';
$password = '--';
$domain   = 'yourdomain'; // domain name without extension
$limit    = 10; // stop processing this script after this number of checks
if (!$_SERVER['argv'][1] || stristr($_SERVER['argv'][1], '.')) {
  die("Provide a domain name (without extension) and an optional limit. Syntax:\n    check-bulk.php somedomain [limit]\n\n");
}
$request = new OP_Request;
$request->setCommand('searchExtensionRequest')
  ->setAuth(array('username' => $username, 'password' => $password))
  ->setArgs(array(
    'limit' => 3000,
    'status' => 'ACT',
    'onlyNames' => true,
  ));
$reply = $api->process($request);
$res = $reply->getValue();
foreach ($res['results'] as $ext) {
  $request = new OP_Request;
  $request->setCommand('checkDomainRequest')
    ->setAuth(array('username' => $username, 'password' => $password))
    ->setArgs(array(
      'domains' => array(
        array(
          'name' => $domain,
          'extension' => $ext,
        ),
      )
    ));
  $reply = $api->process($request);
  if ($reply->getFaultCode() == 0) {
    $res = $reply->getValue();
    echo $domain.'.'.$ext."\t".$res[0]['status']."\n";
  }
  else {
    echo $domain.'.'.$ext."\t".$reply->getFaultCode().': '.$reply->getFaultString()."\n";
  }
  if ($limit && ++$cnt >= $limit) break;
}
?>