/*
 * call-seq:
 *   easy.body_str                                    => "response body"
 *
 * Return the response body from the previous call to +perform+. This
 * is populated by the default +on_body+ handler - if you supply
 * your own body handler, this string will be empty.
 */
static VALUE ruby_curl_easy_body_str_get(VALUE self) {