I've read through the entire thread, and I don't think anyone mentioned the "Cache-Control" header; The as bulletproof as you'll get solution would be with the follow chunk of headers:
Cache-control: no-cache
Pragma: no-cache
Expires: (time)

[download]
The time should be expressed in one of the formats mentioned in section 3.3.1 of RFC2068)

This should catch all variants of agents and intermediaries, however, I expect there are still a few old/badly behaved agents out there...

--
RatArsed

In reply to Re: CGI Caching question by RatArsed
in thread CGI Caching question by chorg

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