A good way to figure out what you need is to telnet to your favorite server which is already sending out similar data.
For example, if you can read the first 15 lines or so of it's response to a proper GET, that'll contain your header.
telnet www.perlmonks.org 80
Trying 206.170.14.75...
Connected to www.perlmonks.org.
Escape character is '^]'
GET http://www.perlmonks.org/ HTTP/1.0
// you'll need to press Enter a few times until you get a return
anyway...
just incase you want a header to just display,
here's one for ya...
HTTP/1.1 200 OK
Date: Tue, 29 Aug 2000 14:00:22 GMT
Server: Apache/1.3.12 (Unix) PHP/4.0.1pl2 mod_ssl/2.6.5 OpenSSL/0.9.5a
Last-Modified: Mon, 24 Jul 2000 13:28:52 GMT
ETag: "179c3-37ee-397c4494"
Accept-Ranges: bytes
Content-Length: 14318
Connection: close
Content-Type: text/html
to out put this to a client, you'd put a CR before and after the header, and start your code after the header.