[cups-devel] lpr and authentication for dnssd backend on Mac

[Andreas Lobbes]

Hello,

I need to access password-protected printers via dnssd backend on Mac. When
using a Mac-specific App for printing (thus it should use Mac-specific
printing APIs), then you need to specify the user/password information for a
particular printer only once, as this information gets stored to the so called
"Keychain" and will be reused on further printouts to this printer.
But that does not function, when using the CUPS console binaries (lpr in
particular). Printing to such a password-protected printer results into a
print job being held in the queue with the status message: "On hold
(authentication required)".

My Question is: Is it possible to pass some Mac-specific Options via lpr, so
that the print job can get through?

FYI: When printing via Mac-specific App, I have found in the job control file
the following option setting: "com.apple.print.JobInfo.PMJobOwner=<username>",
which is the username being used for authentication at remote. My first shot
was just to pass this setting via lpr, hoping that a Mac-specific filter or
the dnssd backend then looks into the Keychain for the corresponding password
and uses it, but nope, that did not function.

Any help appreciated,
Regards,
Andreas