At the PRO meeting yesterday, we review Randy's protocol document
which has lots of operation semantics, which we agreed should be moved
to the Model document. Amongst these was a Boolean "end-document-stream"
input parameter which we also agreed would become a job attribute,
so that you could do a GetAttributes and see if the job stream was
still open or not.
BTW, we also agreed to call things in the request, 'parameters', not
'attributes'. Most input parameters of Create-Job and Print-Job wind
up as attributes on the job object. Parameters are passes in a request
or a response, and attributes exist on an object.
At 00:43 06/18/97 PDT, Scott Isaacson wrote:
>In the Model document, there is language about a "zero length document" in a
>>Send-Document operation that is the "flag". I suppose we do need a flag
>since you might know the document you are sending is the last document and
>it would not be efficient to require another empty Send-Document. But we
>allow for an empty Send-Document for the case that Bob points out where
>the client does not know it is the end until there are no more documents.
>>>>>> Robert Herriot <Robert.Herriot at Eng.Sun.COM> 06/12/97 07:54PM >>>
>Option 1 (flag for last document) is the best and only reasonable solution.
>>Option 3 (end job operation) can be accomplished with Option 1 by
>allowing a document of length zero and the last flag on for clients
>that cannot figure out they are done when they send the last document.
>>> From rturner at sharplabs.com Thu Jun 12 17:13:25 1997.
>>>>> In our current document we have a CREATE-JOB operation that specifies up
>> how many documents we have. Is this an unrealistic requirement for
>> future IPP
>> clients (or drivers) ? Will they always know how many documents are
>> coming when
>> they first do the CREATE-JOB?
>>>> My feeling is that the clients might not know how many documents will be
>> sent, and
>> if that is the case, we need a mechanism for SEND-DOCUMENT to indicate
>> the server that this is the last document for the job. There are at
>> least 3 ways to do
>> this off the top of my head:
>>>> 1. Have a specific SEND-DOCUMENT attribute or parameter that flags a
>> request as the last document for the job.
>>>> 2. Since we are using HTTP 1.1 with persistent connections, just close
>> the TCP
>> connection from client to host indicating the end of the job stream
>> (or last document).
>>>> 3. Have another IPP operation called END-JOB or CLOSE-JOB that
>> encapsulates the job stream within a CREATE-JOB/END-JOB pair.