On Thu, Jun 23, 2022 at 6:42 AM Patrick O'Callaghan <pocallaghan@gmail.com> wrote:
On Thu, 2022-06-23 at 13:02 +0930, Tim via users wrote:
> On Wed, 2022-06-22 at 14:01 -0300, George N. White III wrote:
> > AirPrint was introduced in 2011 to support iPads. 
> > https://openprinting.github.io/driverless/01-standards-and-their-pdls/
> > summarizes the differences in the various Driverless Printing
> > implementations.  PDF is supported across the board, but there are
> > several raster formats and also PDFm which is viewable with PDF
> > viewers, but tailored for the capabilities of specific printer
> > models.
>
> I have a HP printer in that boat.  It proudly proclaims direct PDF
> printing (send it a PDF file, or plug a USB into the front with a PDF
> on it).  But after a lot of digging around you find that it only
> supports a special PDF created by their driver program, no other PDF
> files are supported.

So Non-Portable Document Format ...

PDFm is supposed to work with PDF viewers.  I assume it just adds printer-specific metadata:
things like which paper tray, duplex (double-sided) long or short edge binding, collating, stapling,
etc.

--
George N. White III