[cups] Unable to add a printer

[Znoteer]

Hi,

I think my replies to your first answers and your new reply to me have
crossed in transit.

On Tue, Apr 30, 2019 at 03:43:20PM +0200, Johannes Meixner wrote:
> 
> Hello,
> 
> On Apr 30 13:29 Brian Potkin wrote (excerpt):
> > On Tue, 30 Apr 2019 at 12:39, Znoteer <znoteer at mailbox.org> wrote:
> ...
> > > Bus 001 Device 002: ID 067b:2305 Prolific Technology, Inc. PL2305 Parallel Port
> > 
> > This is the parallel port to USB adapter mentioned by Johannes. You
> > can search with "PL2305 parallel port linux" for advice.
> > https://github.com/apple/cups/issues/4765 is also worth a look at.
> 
> hacks like manual editing /etc/cups/printers.conf with something like
> 
> DeviceURI parallel:/dev/usb/lp1
> 
> may no longer work because the DeviceURI scheme "parallel" is the
> name of the CUPS backend program "/usr/lib/cups/backend/parallel"
> which might be no longer provided in your Linux distribution
> and even if it is provided that program might require to have
> actual parallel port hardware in the computer, but I don't know
> any details here.

I try to avoid hacks, anyway.  Too hard to maintain.
> 
> In general manual editing CUPS config files is bad,
> see "Command-line Tools" in
> https://en.opensuse.org/SDB:CUPS_in_a_Nutshell
> 
> Therefore instead of hacks the right way for special cases
> is to use a custom backend to print with CUPS as described in
> https://en.opensuse.org/SDB:Using_Your_Own_Backends_to_Print_with_CUPS
> 
> What is needed is to verify what kernel device node
> can be used to send data to the printer e.g. via
> 
> echo -en "\rHello\r\f" >/dev/usb/lp0

This command works as root.  It gets printed.
> 
> cf. https://en.opensuse.org/SDB:Installing_a_Printer

Will read.

-- 
Znoteer
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