static bool checkprefixmax(const char *prefix, const char *buffer, size_t len)
{
  size_t ch = CURLMIN(strlen(prefix), len);
  return curl_strnequal(prefix, buffer, ch);
}
static bool checkprefixmax(const char *prefix, const char *buffer, size_t len)
{
  size_t ch = CURLMIN(strlen(prefix), len);
  return curl_strnequal(prefix, buffer, ch);
}