You shouldn't set the expires header to be "now" (update (thanks frodo72): but that code doesn't set the header to be "now", it is converted to an actual date. That's teach me to not test - you only ever get something wrong if you don't test, 99% of the time, if you do test, your test will give the expected result). The spec says that it must be in HTTP-Date format. It does also say that if a client recieves anything that isn't HTTP-Date, then it should treat it as "already expired" - but intentionally triggering error recovery isn't a fantastic idea.

Other caching headers might also come in useful. Caching Tutorial for Web Authors and Webmasters is a worthwhile read.

In reply to Re^2: Automatic page refresh by dorward
in thread Automatic page refresh by Anonymous Monk

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