PHP socket and HTTP post

[Anon]

Object: An html form submits 3 variables, $Login, $Pwd and $Data, to a PHP4 file. The $Login and $Pwd contains alphanumeric and the $Data contains an XML document for a request.
This XML doc must then be posted to an, outside server using https, .asp file with the 3 variables, just like a normal html form submit, but without leaving the current PHP file. The .aps file returns a new XML document, which needs further processing.

Problem: How do I do this?

Tried: Using PHP’s socket functions, but I’ am not sure if whas the right way.

Time is VERY critical, since this one is for my work.

Best Regards

[morphy]

$w_socket=fsockopen($server_ip,$port,&$errno,&$errstr,10000);
if($w_socket)
{
fputs($w_socket,"GET /page.asp?param1=1&param2=2&param3=3 HTTP/1.1\n\n");//every http header u need
while(!feof($w_socket))
{
$RetValue=fgets($w_socket,2048);
flush();
}
}

well u use the socket as a file u put every HTTP request with fputs then with the while loop u read from that "file".... i used this code succesful for an e-comm web site (mmm if i remember i found it in the manual...... maybe u can find more infos....)