You could use CGI::Validate to validate your form entries, although your current method is good too.

For validating ip_address and referrer, you could use this 
$q->param('ip_address', $ENV{REMOTE_ADDR});
$q->param('referrer', $ENV{HTTP_REFERER});

[download]
to set the CGI parameters, then use CGI::Validate.

As for securing the files, why not just write 'newsletter.txt' outside the root of the webserver.

In reply to Re: Subscription form script by tcf22
in thread Subscription form script by Anonymous Monk

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