Bug#926576: ghostscript: printer stopped working: ghostscript fails with ""Unable to determine number of pages"

[Till Kamppeter <till.kamppeter@gmail.com>]

Thanks for reporting this.

I have fixed the problem now by changing the Ghostscript call to count 
pages in a PDF file.

See

https://github.com/OpenPrinting/cups-filters/commit/297cc2d

I found this solution with the help of a bug report to Arch Linux:

https://bugs.archlinux.org/task/62251

There they have found the alternative method and also talked with the 
Ghostscript developers on IRC to confirm the need of the change.

The old call used the undocumented internal "pdfdict" of Ghostscript 
which from Ghostscript 9.27 on is not accessible any more for security 
reasons. Now I use the call suggested in the Arch Linux bug report using
"runpdfbegin".

   Till