interfacing to Authorize.net using AIM method and cURL

[GluedToTheScreen]

I have a small PHP ecommerce site set up using Authorize.net's SIM (simple)
interface. Working fine, but... I'd like to implement their AIM interface
(so visitor's will never see the gateway's URL).

I found a script that does this but requires cURL... and my hosting provider
doesn't support it.

Here is the snippet of the code that uses cURL functions ($data values are
set before this from the purchase form):
$curl_handle = curl_init ();
curl_setopt ($curl_handle, CURLOPT_URL,
"https://secure.authorize.net/gateway/transact.dll");
curl_setopt ($curl_handle, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt ($curl_handle, CURLOPT_RETURNTRANSFER, 1);
curl_setopt ($curl_handle, CURLOPT_POST, 1);
curl_setopt ($curl_handle, CURLOPT_POSTFIELDS, $data);
$response = curl_exec ($curl_handle) or die ("There has been an error
connecting to Authorize.net.");
curl_close ($curl_handle);
It appears that data is being posted to the gateway and information returned
(credit card accepted/declined) and then processed without actual web pages
being displayed.

What is cURL actually doing and can it be done some other way?

Is there any way I can accomplish the same thing without curl libraries...
maybe write my own lower level code? I can certainly post data to the
gateway... and, if I knew how to accept the returned data, can perform the
necessary steps from there. My big blank spot seems to be how to receive
that data response.

Thanks.

Rick

[Appletalk]

Check out this function

# $host includes host and path and filename
# ex: "myserver.com/this/is/path/to/file.php"
# $query is the POST query data
# ex: "a=thisstring&number=46&string=thatstring
# $others is any extra headers you want to send
# ex: "Accept-Encoding: compress, gzip\r\n"
function post($host,$query,$others=''){
$path=explode('/',$host);
$host=$path[0];
unset($path[0]);
$path='/'.(implode('/',$path));
$post="POST $path HTTP/1.1\r\nHost: $host\r\nContent-type: application/x-www-form-urlencoded\r\n${others}User-Agent: Mozilla 4.0\r\nContent-length: ".strlen($query)."\r\nConnection: close\r\n\r\n$query";
$h=fsockopen($host,80);
fwrite($h,$post);
for($a=0,$r='';!$a;){
$b=fread($h,8192);
$r.=$b;
$a=(($b=='')?1:0);
}
fclose($h);
return $r;
}

Posted on http://uk.php.net/fsockopen

I'm sure this will help you out.