public function b2_list_file_names($api_url, $auth_token, $bucket_id, $options = NULL)
        {
            $call_url   = $api_url."/b2api/v1/b2_list_file_names";
            $auth_token = $auth_token; // Obtained from the b2_authorize_account call
            $bucket_id  = $bucket_id; // The ID of the bucket containing the files you wish to list
            $max_count  = $options["max_count"]; // The maxiumum amount of file names to list in a call
            $start_name = $options["start_name"]; // If the specified file name exists, it's the first listed

            // Add POST fields
            $data = array(
                "bucketId"      => $bucket_id,
                "startFileName" => $start_name,
                "maxFileCount"  => $max_count
            );

            // Add headers
            $headers = array(
                "Authorization: {$auth_token}"
            );

            $result = b2_call($call_url, $headers, $data);
            return $result; // Return the result
        }