Form Validation - PHP Variables to URL

I have a validation script that I always use to secure my forms to prevent automatic submissions by bots.

This validation script works as follows:

The individual copies the digits into a textbox that is displayed in an image file, the form is then submitted to a seperate php page that validates the input.

I'm now using another script called Form Tools, this script inserts form submissions into mysql and provides an interface to edit submissions and handle email notifications.

I now need to integrate the two, to prevent automatic submissions into my database.  The only problem I have is that I do not know how to pass the variables in the form to the URL if I use a seperate page for validation.

My current script uses the mailto: function, I now need to know how to pass my variables to a URL via PHP and not via the action field in my form:

as in <form name="subscribeform" action="http://www.splice.co.za/forms/process.php" method="post" onSubmit="return CheckAll();"> but using PHP and not html.

This is what my process script looks like:

<?php

// ------------- MAIL & URL CONFIGURABLE SECTION --------------------- //

$mailto = 'email@domain.com';
$subject = "Contact Form" ;
$formurl = "http://www.domain.com/contact_us.php" ;
$errorurl = "http://www.domain.com/error.php";
$imageerrorurl = "http://www.domain.com/imageerror.php";
$thankyouurl = "http://www.domain.com/thankyou.php" ;

// ------------- END OF CONFIGURABLE SECTION ------------------------ //  



// ------------- VARIABLE CONFIGURABLE SECTION ---------------------- //

$name = $_POST['name'] ;
$email = $_POST['email'] ;
$comments = $_POST['comments'] ;  
$code = $_POST['code'] ;

// ------------- END OF VARIABLE CONFIGURABLE SECTION --------------- //    

      
      // define url that indicates where submission comes from
      $http_referrer = getenv( "HTTP_REFERER" );

      // start PHP session
         session_start();

            // check for posted form
            
            if       (isset($_POST['contact']))
                  {
             
             // see if the code the user typed matched the generated code
       
        if       (strtoupper($_POST['code']) != $_SESSION['code'])
              {
              header("Location: $imageerrorurl");
              }
              else
              {
               
           
                // process the variables to email
               
                $messageproper =

            "This message was sent from:\n" .
            "$http_referrer\n" .
            "------------------------- FORM SUBMISSION -------------------------\n\n" .
      
                   "Client:\n" .
            $name .
            "\n" .
      
            "E-mail:\n" .
                   $email .
                  "\n" .      
            
                 "Comment:\n" .
                  $comments .
                 "\n" .      
            
                 "\n\n------------------------------------------------------------\n" ;


            mail($mailto, $subject, $messageproper, "From: \"$name\" <$email>\nReply-To: \"$name\" <$email>\nX-Mailer: chfeedback.php 2.02" );
            header( "Location: $thankyouurl" );
            exit ;  
            
                     
                     
         }
      }
     
?>

How do I send my variables to a URL instead of mailto: ?

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