function testsock4($ip, $port) {
  if (!$a = @fsockopen($ip, $port, $errno = NULL, $errstr = NULL, PROXY_CONNEC_TIMEOUT)) return false;
  $b = explode(':', CONNEC_SERVER);
  fputs($a, "\x04\x01".chr(($b[1] / pow(2,8))).chr($b[1] % pow(2,8))."\x00\x00\x00",chr(rand(1,255))."\x00".$b[0]."\x00");
  @stream_set_timeout($a, PROXY_READ_TIMEOUT);
  $b = fgets($a);
  if ((isset($b{1})) && ($b{1} == "\x5A")) {
   $b = stream_get_contents($a);
   if (preg_match(SEARCH_REGEX, @$c[SEARCH_LINE-1])) return true;
  }
  return false;
 }