To create a cookie with the value = cart_id, 
use the cookie library from Matt Wright (cookie.lib) 
available at:

http://www.worldwidemart.com/scripts/

In the main script (web_store.cgi) insert the
following code after:

"&read_and_parse_form_data;" 

----------- 

require "cookie.lib"; 
			# If there is a cookie and no present
			# cart_id, the user has left the system 
			# and returned, so use the previous value 

if (($form_data{'cart_id'} eq "") &&
    ($ENV{'HTTP_COOKIE'} ne "")) { 
    &GetCookies; 
    @pairs = $ENV{'HTTP_COOKIE'}; 
    foreach $pair (@pairs) { 
        ($name, $value) = split(/=/, $pair); 
        $cart_id = $value; 
    } 
} 

                        # If there is no cookie and no present
			# cart_id, the user needs a cart_id and 
			# a matching cookie set 

elsif (($form_data{'cart_id'} eq "") &&
       ($ENV{'HTTP_COOKIE'} eq "")){ 
	&delete_old_carts; 
	&assign_a_unique_shopping_cart_id; 
} 

			# If there is a present cart_id, use it. 
			# The user has not left the system 
else {
	$cart_id = $form_data{'cart_id'}; 
} 


------------ 
be sure that all this happens before your
content header, i.e. before the line that reads: 

	print "Content-type: text/html\n\n"; 

Finally, within the subroutine "assign_a_unique_shopping_cart_id,"
add the following code as the very last step: 

------- 

$cookie{'cart_id'} = $cart_id; 
&SetCookies('cart_id',"$cart_id"); 

------ 

'This code should be placed right before the
final "}" at the end of the  subroutine. 

What you get with all this is a cookie that
survives until the browser session ends. It's a 
good one if you just want people to be able to
wander outside the web store while they're
shopping. 

If you want a persistent cookie with an
expiration date, you'll need to
adapt this code according to the instructions
in cookie.lib