I think that Apache (I assume you're using Apache; in this kind of context if your web server is anything else you should say so) by default will send Pragma: no-cache along with the output of a CGI script, but if someone has changed the value of CacheNegotiatedDocs in the configuration, this may not be happening. In that case, you could work around it by printing out that header yourself.

If you aren't sure whether the pragma header is being sent, you could use WWW::Mechanize to find out.

If the pragma is being sent and the web browser is ignoring it, I'm not sure what to suggest other than adding a random element to the query string to make the url unique each time, but that would require that the HTML document be generated each time, so it won't help you if the image is designed to be used from static HTML documents (e.g., if it's a counter).

Sanity? Oh, yeah, I've got all kinds of sanity. In fact, I've developed whole new kinds of sanity. Why, I've got so much sanity it's driving me crazy.

In reply to Re: Calling CGI but not caching by jonadab
in thread Calling CGI but not caching by pickledegg

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