[cups] Handling of "Installable Options" in user applications

[Brian Potkin]

On Mon 07 Sep 2015 at 15:48:27 +0200, Johannes Meixner wrote:

> On Sep 7 13:49 Brian Potkin wrote (excerpt):
> >A queue set up with Tea4CUPS can be set up as a raw queue.
> >I suppose a user could have knowledge of options from
> >elsewhere and *specify* them for a job.
> 
> But then there must be also a non-raw queue
> that does the actual print job processing.
> 
> To avoid that users use that non-raw queue directly
> it would have to be set up so that normal users are
> not allowed to submit print jobs to that queue.

That's correct. The non-raw queue is not shared.

> >... how is the system adjusted to deal with non-PPD
> >specific options (like the ones provided by cups-filters)
> >to make sure they are applied?
> 
> Basically - as far as I know - you cannot make settings
> in the system for non-PPD options.

Which is fine until the administrator decides to devote a printer solely
to the printing of booklets using the facility in the pdftopdf filter of
cups-filters:

  lpadmin -p bookletq -v <etc> -E -o booklet -m <PPD>

A canny user can still send

  lp -d bookletq -o 'nobooklet Duplex=None' <file>

I'd see the Tea4CUPS hooks and the non-raw, "hidden" queue as a useful
technique if the administrator is determined to have her own way. :) 

[Snip]

> Assume a user submits a job with:
> 
> $ echo hello | lp -d queue_name -o rotate=90degrees
> 
> When there is only one filtering program that understands
> and uses the rotate=90degrees option, then the output
> is what the user expects.
> 
> But when two filtering programs understand and use the
> rotate=90degrees option, then the output is probably
> not what the user expects (i.e. two times rotated
> by 90 degrees).

All further complicated by the different results using '-o landscape'
or '-o orientation-requested=4'. The first option can rotate a page
clockwise or anticlockwise depending on what *LandscapeOrientation is
in the PPD file. The second always rotates a page anticlockwise. Throw
pdftopdf's autorotaion into the mix (it rotates a page anticlockwise)
and you have to think carefully about what your expectations should
be.

Regards,

Brian.