Hello, I'm looking for a little assistance on a script that I've been working on. I'm trying to figure out how to check if values are being passed from one script to another...and if the values are not passed properly give an error to the user. Here's the snip: 
use CGI;
my $q = new CGI;
$user_id=$q->param('userid');
$user_email=$q->param('useremail');
$user_name=$q->param('username');

$give_access = "<a href=give_access.cgi?setsig;user=$user_id;email=$us
+er_email;passwd=$user_password;multiname=$multiname>";

[download]
I want to give an error message if the user tries to access the program directly "give_access.cgi", without using a standard form that would provide the userid, useremail, and username. I've tried the following but keep getting a error-500: 
 if ($q->param('userid'))
         {
         }
 else
         {
         &error_message("You need to use the form to access this progr
+am!");
         }

sub error_message
 {
 local($e) = @_;
print <<"END";
<html>
<head>
<title>Error</title>

<center>
Error. The error seems to be:<p>
$e

END
exit;
}

[download]
Any suggestions? Thanks! Lis.

In reply to Value Check by lisaw

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