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Reprobate
09-11-2004, 10:08 PM
I've got a whole bunch of Code 304's (Not Modified) coming up in my site stats.

even more than the 404's.

in the first 9 days of this month i've gotten 26,465 404's. which sound slike i've got a lot of broken links throughout the site, but i believe a lot of them are due to people typing in URL's with the hope of finding extra unlisted pages.

and i've got 30,638 304's. but i don't know what a 304 is.

i went looking it up and found the following.


304 Not Modified
If the client has performed a conditional GET request and access is allowed, but the document has not been modified, the server SHOULD respond with this status code. The 304 response MUST NOT contain a message-body, and thus is always terminated by the first empty line after the header fields.

The response MUST include the following header fields:

- Date, unless its omission is required by section 14.18.1
If a clockless origin server obeys these rules, and proxies and clients add their own Date to any response received without one (as already specified by [RFC 2068], section 14.19), caches will operate correctly.

- ETag and/or Content-Location, if the header would have been sent
in a 200 response to the same request
- Expires, Cache-Control, and/or Vary, if the field-value might
differ from that sent in any previous response for the same
variant
If the conditional GET used a strong cache validator (see section 13.3.3), the response SHOULD NOT include other entity-headers. Otherwise (i.e., the conditional GET used a weak validator), the response MUST NOT include other entity-headers; this prevents inconsistencies between cached entity-bodies and updated headers.

If a 304 response indicates an entity not currently cached, then the cache MUST disregard the response and repeat the request without the conditional.

If a cache uses a received 304 response to update a cache entry, the cache MUST update the entry to reflect any new field values given in the response.

http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html (http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html)


is there anyone here that can translate that into plain English for me?

repeat
09-11-2004, 10:20 PM
It just means the document has not modified since the last time the user requested it.

Thank god for the 304 too, because otherwise you would have to download every image every time when browsing around a site. The 304 makes it so image files (and static html in some cases) can be pulled from the user's cache if the file has not changed.

Reprobate
09-11-2004, 10:34 PM
It just means the document has not modified since the last time the user requested it.

rep for repeat. i repeat, rep for repeat.