[Openicc] Gutenprint obstinacy

[Robert Krawitz]

On Fri, 17 Jun 2011 03:38:20 +0200, edmund ronald wrote:
>
> I am starting to modify some prototype Gutenprint code written by Robert,
> that loads and saves inking options, and trying to figure out how it
> interacts with the underlying system (my modifications seem to be breaking
> the defaults override). Could someone who knows Ubuntu explain to me how and
> where the defaults for printing get *stored*, be it when they are set from
> the Print administration utility, be it when they are set from the CUPS
> interface? I assume there is an initial "stemcell" PPD, then a "live" PPD,
> and then some user-specific options which are squirelled away somewhere?
> Where are all tehse things, how can one quickly figure out what would be
> passed through in the end?

In general, there is a baseline per-model PPD file that's either in
/usr/share/cups/model or generated on the fly.  When you create a
printer queue, that file is copied into /etc/cups/ppd, where it is the
"live" PPD.  Once the "live" PPD fle exists, the "stemcell" one is no
longer of interest; CUPS doesn't use it on the fly.

Administrative commands (such as http://localhost:631 or an
administrative utility) will affect the "live" PPD file.  User
commands (such as lpoptions) will create or modify a file named
~/.lpoptions.  I presume that those options are extracted and passed
into CUPS, where they are placed on the command line for the actual
filter.

Gutenprint's debug output notes which options are passed via the
command line and which come from the PPD file.  Command line options
(which may not be passed by the "command line" of the user program)
override PPD file settings.

> It depends upon "how they are set by the user".  If they are set via
>> localhost:631 or some similar mechanism, they are changed in the PPD
>> file.  If they are set by lpoptions or some other user-specific
>> mechanism, they are stored in ~/.lpoptions (and probably passed on the
>> command line).
>>
>> > On Thu, Jun 16, 2011 at 5:42 PM, edmund ronald <edmundronald at gmail.com
>> >wrote:
>> >
>> >> where are the CUPS default system options set by the user recorded? They
>> >> must be somewhere?