[cups.bugs] [LOW] STR #2824: Misleading error reporting.

Kim_Bruning kim at bruning.xs4all.nl
Mon May 19 19:51:52 PDT 2008


[STR New]

I have an Epson Stylus 3850

I'm not sure if this is low priority or critical priority. I've had many
issues with misleading error reports (or a lack of error reports at

On installing cups, it auto-detected my printer, but no matter what I
tried, the printer would only print gibberish text. After trying almost
every possibility I could think of (including recompiles from source,
etc), it finally turned out that the problem was merely that an actual
valid driver for my printer _hadn't even been installed yet_. CUPS hadn't
deemed it necessary to detect or report this rather show-stopping problem.

More recently, CUPS reported a backend USB problem. Once again, I tried
many different approaches, (including a recompile in case there were
broken libraries, examination of /dev/usb/* permissions, etc)  and the
problem simply wouldn't clear. Each time jobs seem to silently vanish off
of the job queue. Finally, at the end of my rope, I decided to click on
"start printer" (wasn't the printer already started?) ... and the problem
immediately cleared and the printer started printing all the jobs that I
thought had failed. ARGH!

Googling for error messages (when they do occur) leads to all kinds of
obscure sites, but not to cups documentation afaict (maybe I'm missing
it?). In both cases the show-stopper was not the performance of a single
line of source code in cups, but rather the fact that it was far from
obvious what the problem was, or how to resolve it, eventually leading the
operator to resort to trial and error. 

So this appears to be a combination UI/Documentation problem. I'm not sure
if this is symptomatic, or that these are just 2 cases that both just
happened to me.

If there are (potential) problems, cups should provide clear warnings and
errors to the user, that properly explain the problem in a user(/operator)
legible and solvable way, and also that these error messages are clearly
documented, including what the root cause is and how to resolve the issue.
In situations where something can (potentially) go wrong, cups must warn
that there may be a problem. In error situations, it must be much more
clear that cups is currently dealing with an error.

In all cases where there are warnings and errors reported to the user,
cups should provide some kind of clue Where The Heaven one can Read The
Fine Documentation to resolve the issue at hand.

Link: http://www.cups.org/str.php?L2824
Version: 1.2.12

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