[cups.general] cups prints DOUBLE ofspecified copies

[Michael Sweet]

Helge Blischke wrote:
> I think the squaring of the number of copies is due to a conflict between the
> pstops filter (which tells the printer's PS interpreter to produce multiple copies)
> and the IPP backend which tells the printer ro do multiple copies by specifying
> the appropriate job attibute within the IPP request.
> 
> I've not checked if there is a fix of this issue in 1.2

Not specifically, no.

If you are printing a filtered file via IPP, then we omit the copies
attribute from our outgoing request - the file is generally of type
"application/vnd.cups-postscript" and already contains the number of
copies command (or duplicated pages, as needed) embedded in the data
stream.

If you are printing an unfiltered (or raw) file via IPP, then we check
whether the remote server supports copy generation, and either pass
copies set to the number of copies requested, or duplicate the print
data N times to generate the copies (this is done specifically to
support copy generation for HP printers via IPP).

Now, if you print a PS file which sets the number of copies using PS
commands, it is possible to get N*M actual copies printed.  Unless
an app uses the %%Begin/EndFeature DSC comments around the number of
copies command, there isn't anything we can do to stop this from
happening.  Similarly, if you print a PS file with "-oraw", then the
PS filter isn't involved and copies will be multiplied.

In short, there are some edge cases which can cause this behavior,
but for normal printing this should never happen with the standard
CUPS software.  Don't depend on Apple's version of CUPS working the
same way...

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