private function headerCallback($ch, $header)
{
$_header = trim($header);
$colonPos = strpos($_header, ':');
if ($colonPos > 0) {
$key = substr($_header, 0, $colonPos);
$val = preg_replace('/^\\W+/', '', substr($_header, $colonPos));
$this->responses[$this->getKey($ch)]['headers'][$key] = $val;
}
return strlen($header);
}