[cups.general] IPP Request and response comparison

[Mike Sweet]

On Apr 19, 2011, at 6:01 AM, rajkumar <raj.acts18 at gmail.com> wrote:
> If i send a request to CUPS server and CUPS server return a response.
> How do i know that which request's response comes,Because some where return that using request id,
> But
> http://tools.ietf.org/html/draft-ietf-ipp-protocol-04 on this link it is written that

Please don't develop against expired drafts if the IPP specification. The published specification is here:

    http://tools.ietf.org/html/rfc2911

WRT the request-id value, you can pass in any positive integer up to 2^31-1 in the request, and the same number is supposed to be returned in the response. In general, the request ID is usually ignored by software based on libcups since you can only have a single request in flight for a given connection to the server.

> ...
> and i tried that i update request id with some random number in request header and i didnt update request id in response header with original request id.and job got printed.so i think that request id is not checked by client....

The request-id returned in the response will be the same as the request as long as it is valid (1 to 2^31-1).

> "My question is that how do i know that particular response is for particular request."

Aside from the request-id, you know the response you read from a http_t connection will belong to the request you just sent on that connection.