Re: [gentoo-user] What's with foomatic-filters and cups-filters?

[Alan McKinnon]

On 09/06/2014 12:28, Alan Mackenzie wrote:
> Hi, Alan.
>
> On Sun, Jun 08, 2014 at 11:47:32PM +0200, Alan McKinnon wrote:
>> For Alan Mackenzie's benefit, a little back story:

[...]

>> Many years ago, HP developed a fancy printing language for their laser
>> printers called PostScript[1].
>
> Wasn't it Adobe?

Yes, I believe you are right. this old brain isn;t what it used to be

[...]

>> meanwhile, printers shifted over to USB away from parallel ports  and
>> this needed new drivers. Plus there's two way to do it: do the USB part
>> of the printing in userspace and only use the kernel for regular USB
>> work, or put the whole thing in the kernel. Needing more drivers. last I
>> looked, there were still some serious issues with the options to have it
>> all in the kernel.
>
> This is the CONFIG_USB_PRINTER, which if I remember correctly, must be
> either on or off depending on other things you might have configured.  I
> have been confused about this in the past.  Incidentally, my printer has
> a parallel port which was still in use until I got my new box in 2009.

That's the one. Very very confusing at the time and I recall it clearly
- the kernel config help text was as far from helpful as one can get.
Lucky for me, I found a howto by someone who understood and that sorted
it for me.

[...]

>> And I haven't even touched on CUPS' "feature" that requires you to
>> delete and re-add back all your printers after any remerge. Ask Dale
>> about this, he's the resident expert and he's even figured out how to
>> get hplip to work.
>
> I don't seem to need hplip at the moment.  My emerge of cups last night
> (to 1.7.1) didn't need me to reinstall my printer.

As I understand it hplip installs drivers for HP printers and is able to
figure out what you have and which driver you need. I doubt it is a
dependency of anything, it looks more like something you install if you
want it and need it

[...]


> My main problem was with emerge.  The fact that various printing packages
> were blocking eachother was only apparent in the 147k line debug output,
> not in the normal messages printed to stdout/stderr.

You have the bad luck to have picked exactly the wrong time to update a
Gentoo box after a long time away. A *lot* has happened in the tree over
the past several months, especially sub-slots that have now come into
their own.

Sub-slots are actually a good idea, and time will tell if the
implementation is also a good idea. There's many benefits, not least of
which is that every huge package your have like libreoffice probably
doesn't need updating every time a line of code changes in icu. Not
needing @preserved-rebuild is a small bonus, not something I care much
about. And I don't mind running perl-cleaner once a year with a major
version perl upgrade. I *do* mind forgetting to run perl-cleaner and
being caught out - sub-slots help with that.

Unfortunately portage has always been a tad obtuse with it's output, and
leans heavy towards a fatal design flaw to the user - too much of the
internal implementation shows up in the output wording. Recent !arch
version deal with this, that "no parents that aren't satisfied in this
slot" message is gone (no-one ever knew what that meant) and is replaced
with clever output that prints version numbers and operators (<, >= and
so on) in colour with neat carat symbols "^" below, that point to what
is important.

I strongly recommend you set portage to use ~arch, it is good code these
days and while it doesn't remove the complexity of the tree, it does
make a much better job of telling you what is going on and what it needs
from you to proceed.


-- 
Alan McKinnon
alan.mckinnon@×××××.com