[cups.general] Can CUPS pass through the printer status somehow

[Michael Sweet]

Ambrose Li wrote:
> On 14/12/06, Michael Sweet <mike at easysw.com> wrote:
>> Ambrose Li wrote:
>> > This has nothing to do with the status byte or anything that deals with
>> > the actual printing itself, but what the printing system does when the
>> > user requests "what is in the queue".
>>
>> THE LPD BACKEND DOES NOT EXIT UNTIL IT GETS CONFIRMATION FROM THE
>> REMOTE SERVER THAT THE JOB HAS BEEN RECEIVED.  Thus, the job will
>> stay queued until the printer says the job has been handled.  Thus
>> the job will show up in the lpq/lpstat output until the job has been
>> handled by the printer.
> 
> Sorry if you don't understand what I am trying to say. I must have
> very bad and unclear writing.
> 
> Let my repeat, the confusion has nothing to do with RECEPTION by the 
> printer.
> 
> When the printer has completely received the job, the job could still
> be queued inside the printer.

True, however the CUPS backends do everything they can to wait until
that job is finished on the remote end.  The fact the LPD and
AppSocket protocols provide no reliable way to do this is not the
fault of CUPS, and all you get with the old LPD/LPRng spoolers is
the hack of showing the remote queue.  It is easy for you (as a
human being) to interpret the plain text status report coming back
from the printer, however it is not easy for the LPD backend to do
the equivalent of an lpq on the remote printer and determine whether
the job is still queued.

Moreover, because network print servers (internal and external) often
operate separately from the print engines (even for internal HP
JetDirect interfaces!), the information you get from the device is
not all that accurate... :(

-- 
______________________________________________________________________
Michael Sweet, Easy Software Products           mike at easysw dot com
Internet Printing and Document Software          http://www.easysw.com