#!/usr/bin/perl
#
# evs.pl
#

    # use the CGI mod
    use CGI;
    use Email::Valid;

    # new CGI
    my $CGI = CGI->new();

    # define variables
    my $cmd = $CGI->param('cmd');
    my $account = $CGI->param('account');
    my $email = $CGI->param('email');

    if ($cmd eq "activate") {
        &activate;        # activate the account
    }
    else {
        &verify;            # verify the email address and send email
    }

    # exit
    exit;

# Verify
sub verify { 

    # make sure an email was entered
    if ( ! $email ) {    
        &error(" No Email Address was entered! ");
    }
    
    # make sure it is a vaid email address
    if ( ! Email::Valid->address($email) ) {
        &error(" An invalid Email Address was entered! ");
    }

    # Get a new account ID
    open(FILE, "id.txt") || error("No ID file");        # Make sure yo
+u change the path
    my $ID = <FILE>;
    close(FILE);

    # Increase the ID by one
    $ID++;

    # Rewrite the ID file
    open(FILE, ">id.txt") || error("Can't write ID File");
    print FILE $ID;
    close(FILE);

    # Add this email to the 
    # email db
    open(DB, ">>email_db.txt") || error("Could not write to DB");
    print DB "$ID|$email|0";        # The 0 is a status flag showing
    close(DB);            # that the email address is not activated

    # Send them an email with
    # the link and new ID.
    # I don't know what email server
    # you're useing but I assume you do.
    # The link you need will be
    # www.page.com/evs/evs.pl?cmd=activate&account=$ID&email=$email

    # then finish with a message
    # to the user.
    # ...

    exit;
}

# Activate
sub activate {

    # Make sure they included
    # an account ID and Email Address
    if ( ! $account || ! $email ) {
        &error(" An Account ID or Email Address was not included ");
    }

    # Open the db
    open(DB, "email_db.txt") || error("Could not open Email DB");
    my @emailDB = <DB>;
    close(DB);

    # keep the db
    my @keepDB = ();
    
    # found flag
    my $found = 0;

    foreach (@emailDB) {
        chomp($_);
        my ($db_ID, $db_email, $db_status) = split(/\|/, $_);

        # Match the email
        if ($db_email eq $email) {

            $found = 1;            # We have found the Email    
        
            # Check to match the ID
            if ($db_ID eq $account) {
                $found = 2;        # Email found and ID matches
            }

        }
        else {
            push (@keepDB, $_);        # Return to db if it's not the 
+email
        }
    }

    # Check for some errors
    if ($found == 0) {
        &error(" Email Address not in our Database! ");
    }
    elsif ($found == 1) {
        &error(" The Account ID was incorrect! ");
    }

    # ReWrite the db to show the this Email
    # Address has been been activated
    open(FILE, ">email_db.txt") || error("Could not write email db");
    print FILE "$ID|$email|1\n";
    foreach (@keepDB) { print FILE "$_\n"; }
    close(FILE);

    # Now you can finish the program
    # as you wish.

    exit;

}

# Errors
sub error { 

    # get the error message
    my($error_msg) = @_;

    # print the page header
    print $CGI-header();

    # print the error
    print $error_msg;

    exit;

}
[download]

Well, you asked:

• ALWAYS check the return value from open(); you're inconsistent in your error checking
• You use local when you mean my in the error routine.
• You slurp the file rather than reading line by line (granted that if you get to point that that would be an issue you'd really want a real database anyhow . . .)
• You don't do any sort of file locking to guarantee that you don't clobber the database if multiple people hit simultaneously (or close enough to simultaneously)
• eq is for strings, == is for numeric comparisons.

I'll stop there.

thank you for the help. just one question. the only reason i didn't use file locking was that it was my understanding that not all platforms use file locking in the same way, and as the original question did not say what platform they were using so i left it out.

Oops, that's not what I meant. Let me try to explain again.. I know how to make the link and email it to the person, what I don't understand is how to do things once they click the link. Ie. the account=$ID so when they click on the script it will tell the script to write $ID to another file. How do I activate just that one piece of code once they click on the link? Thanks

"Age is nothing more than an inaccurate number bestowed upon us at birth as just another means for others to judge and classify us"

sulfericacid

If you mean that you want to get the value of the account variable passed in the URL, then you should look at the param() function in the CGI module.

Arjen