Howdy monks,

I am on windows (xp), 5.8.0. I am writing a CGI. I want to add a button that will allow users to start a script running on the server. This script does some DB updates, then e-mails them when the updates are complete. Both server and users are behind a firewall, so security isn't critical. I have a few basic questions:

• How do I ensure only one copy of my program runs at a time? I had planned on having a "flag" file that indicates if a program is running or not. Other programs would just sleep while this flag file is present.
• What are the main security concerns with my approach?

Anyone have any suggestions/advice on how to go about this kind of thing?

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