Hello, I am now learning Perl for two months. Until now, I am doing well. Most of the time, I can solve problems myself just by reading textbook. Now I have a trouble for the first time. I typed exactly what the textbook example shows, but I can not create/open a DBM database. I would like to know why.... I tested from command line, but there were no errors, but no response. Just the prompt appeared.

This is a program that accept the visitor's name and e-mail from an html page, and then store them in a DBM database. Or, if the user wants to remove his/her info from the mailing list, the program remove them. Here is the code: 
#!/usr/bin/perl
#band.cgi - saves data to and removes data from a database
#creates appropriate dynamic Web pages
print "Content-type: text/html\n\n";
use CGI qw(:standard -debug);
use SDBM_File;
use Fcntl;

#prevent Perl from creating undeclared variables
use strict;

#declare variables
my ($button, $name, $email);

#assign values to variables
$button = param('Button');
$name = param('Name');
$email = param('Email');

if ($button eq "Put Me On Your Mailing list") {
        add();
}
elsif ($button eq "Remove Me From Your Mailing List") {
        remove();
}
exit;

#*****user-defined functions*****
sub add {
        #declare variable
        my %mail;

        #open database, add record, close database
        tie(%mail, "SDBM_File", "maillist", O_CREAT|O_RDWR, 0666)
                or die "Error opening maillist. $!, stopped";
        $mail{$email} = $name;
        untie(%mail);

        #create Web page
        print "<HTML>\n";
        print "<HEAD><TITLE>The Jeffrey Sikes Band</TITLE></HEAD>\n";
        print "<BODY BGCOLOR=silver>\n";
        print "<FONT SIZE=5>\n";
        print "<H1>The Jeffrey Sikes Band</H1>\n";
        print "Thank you, $name. We will send the monthly \n";
        print "newsletter to $email.\n";
        print "</FONT></BODY></HTML>\n";
} #end add

sub remove {
        #declare variables
        my (%mail, $msg);

        #open database
        tie(%mail, "SDBM_File", "maillist", O_RDWR, 0)
                or die "Error opening maillist. $!, stopped";

        #determine if user's information is in the database
        if (exists($mail{$email})) {
                delete($mail{$email});
                $msg = "Thank you, $name.  We have removed your ";
                $msg = $msg . "information from our mailing list.";
        }
        else {
                $msg = "You are not on our mailing list.";       
        }

        #close database       
        untie(%mail);

        #create Web page
        print "<HTML>\n";
        print "<HEAD><TITLE>The Jeffrey Sikes Band</TITLE></HEAD>\n";
        print "<BODY BGCOLOR=silver>\n";
        print "<FONT SIZE=5>\n";
        print "<H1>The Jeffrey Sikes Band</H1>\n";
        print "$msg\n";                 
        print "</FONT></BODY></HTML>\n";
} #end remove

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In reply to I can't connect to DBM Databases by fromjp

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