Re: [gentoo-user] Network printer not being found

[Michael]

On Friday, 30 October 2020 16:49:31 GMT Peter Humphrey wrote:
> On Friday, 30 October 2020 11:51:32 GMT Michael wrote:
> > You need to add your user to the lpadmin group.
>
> All right. I've never had to do so before, but I have now. I've also set
> USE=zeroconf on /net-print/cups and remerged it. Both cupsd and cups-browsed
> are in the default run level. I've even tried connecting via USB-2; when I
> plug it in I get this in syslog:
>
> Oct 30 15:51:37 peak kernel: usb 3-7: new high-speed USB device number 9
> using xhci_hcd
> Oct 30 15:51:37 peak kernel: usblp 3-7:1.1: usblp0: USB Bidirectional
> printer dev 9 if 1 alt 0 proto 2 vid 0x043D pid 0x0300
> Oct 30 15:51:37 peak kernel: usbcore: registered new interface driver usblp
>
> That all looks okay to me, no? But still cups can't see the printer.

We're confusing means of communication with the printer, or I am.  The in-
kernel USB Printer support is deprecated and most printer software no longer 
support it.

Instead just the USE="usb" flag when compiling cups should allow you to 
communicate with USB ports on printers and the cupsd GUI should show the 
printer when plugged in to a USB port on the PC.  If you have compiled the USB 
Printer support as a module you'll need to blacklist it so it doesn't load.


> I found a way, eventually. I had to declare the printer manually, under Add
> Printer. I chose ipp and gave it the URL ipp://<ip-addr>/ipp/print.

URLs imply a network connection using an ethernet cable, which is what I 
assume you were trying to set up in the first instance.  Avahi/zeroconf/upnp 
will announce the printer on the network and as long as cups is compiled with 
USE="zeroconf" it should show up when you go to Administration > Add Printer.


> It was
> found instantly and I could set the paper size. But when I print an Amazon
> return label with Firefox, I get just the text with a blank, framed box
> where the QR and bar codes should be.
>
> Google-chrome printed it though.

This is a browser + printing CSS if one is made available by the website.  
Browsers have different default printing settings, including or excluding 
background images, background colours, etc.  Google-chrome happens to work on 
this occasion, but the web developer ought to have done a better job by also 
providing their preferred CSS for print jobs.


> Emerge -pv firefox returned this:
> www-client/firefox-82.0.2:0/82::gentoo  USE="clang dbus gmp-autoupdate
> hwaccel openh264 pulseaudio system-av1 system-harfbuzz system-icu
> system-jpeg system- libevent system-libvpx system-webp -debug -eme-free
> -geckodriver -hardened - jack -lto -pgo -screencast (-selinux) -wayland
> -wifi" L10N="en-GB ..."
>
> Am I missing something important from that?

Nothing obvious jumps out, but half of these USE flags do not mean much to me.  
:-/

More knowledgeable contributors on FF compile options should be able to chime 
in.