[nycphp-talk] PHP pages cache in spite of header() - ideas?

Chris Shiflett shiflett at
Sat Aug 2 12:56:04 EDT 2003

--- Christopher Hendry <chendry at> wrote:
> I may have a beer or two in me

So things should make more sense to you than the rest of us. :-)

> isn't cacheing a client (or proxy) side thing, thus
> independent of PHP?

Any Web agent can cache resources, so caching can be on the client, server, or
any intermediary (such as a proxy). Even with client caching, PHP can play a
significant role, because it allows you to modify the HTTP headers sent in the
response. Whether interpreted correctly or not, the HTTP headers in the
response are what these agents use to determine whether to cache the response.

Pertaining to your comment about the differences between Mozilla and IE, I sent
an email to this list a few months ago where I speculated about one legitimate
reason for such discrepancies. You can read it here:

Hope that helps.


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