Connection close header with PHP?

Question

For example:

curl_setopt($ch, CURLOPT_URL, "$page");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_NOBODY, 0);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, NULL);

Is there a "Connection: close" header variable I could set?

Also what about a "connection: keep-alive" setting?