[cups.general] How do I force duplex when printing?

[Mike Kasick]

Hi folks,

I'm running CUPS 1.3.11 on Debian sid.  I have a Brother HL-5250DN printer
for which, I want every print job to print duplex whether they specify to
or not.

Thus far I've configured the printer, through CUPS, to print duplex by
default (i.e., PPD contains "*DefaultDuplex: DuplexNoTumble").  This works
just fine for print jobs I submit on my Linux machines as they don't
otherwise specify any contradictory duplex options.

I also have a Windows machine with the CUPS Test Driver v6 that prints via
ipp.  Previously, it would also print duplex regardless of what the duplex
settings were on the Windows machine (which, as I understood, were
irrelevant since the driver was unaware of any duplexer).

However, as of recent, the Windows machine now always prints simplex.  I'm
not sure if this is an incidental part of the Windows PostScript driver
being updated, or if it's somehow related to a prior update of Debian CUPS.
But the point is that every job I submit from the Windows machine contains
the stanza "<</Duplex false>>setpagedevice", which disables duplexing.  I
can't seem to change this in the Windows driver since it complains about
the lack of a duplexer.  But frankly, I'd rather CUPS just override any
duplex settings regardless of what the Windows postscript file specifies.

So is it possible to have CUPS override the duplex options when I print
from Windows?  If so, what needs to be done to make this happen?

I tried Google to see if there was a howto for this or something, but most
of what I found are folks complaining that CUPS overrides their Windows
driver settings when they don't want them to--so I made no progress there.
If anyone has a link or something like that, it would be greatly
appreciated.

Thanks everyone!
see