Cups not working -- lpinfo: bad file descriptor

[RiccardoP]

Hello everyone! Probably after some update, I do not manage to print anymore. I tried several times to start and enable the various cups.service, cups.socket and cups.path, but with no success…

I can see my printers from the CUPS Web Interface, and I manage to print test pages, but when I access any program with printing capabilities, the only printer I see is the “Save to PDF” one.

I am sorry if the question is trivial, but I did not manage to find any solution by playing around myself. Thank you very much!

[Mirdarthos]

Hi @RiccardoP, and welcome!

Please provide the output of:

systemctl status cups

and

sudo grep -i name /etc/cups/cupsd.conf

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Additionally

If your language isn’t English, please prepend any and all terminal commands with LC_ALL=C. For example:

LC_ALL=C bluetoothctl

This will just cause the terminal output to be in English, making it easier to understand and debug.

[RiccardoP]

Thank you very much Mirdarthos!

@Mirdarthos

systemctl status cups

~ >>> LC_ALL=C systemctl status cups                                                                                                                           

* cups.service - CUPS Scheduler
     Loaded: loaded (/usr/lib/systemd/system/cups.service; enabled; preset: disabled)
     Active: active (running) since Fri 2023-11-17 17:09:33 CET; 1min 22s ago
TriggeredBy: * cups.path
             * cups.socket
       Docs: man:cupsd(8)
   Main PID: 765 (cupsd)
     Status: "Scheduler is running..."
      Tasks: 1 (limit: 19035)
     Memory: 5.7M
        CPU: 49ms
     CGroup: /system.slice/cups.service
             `-765 /usr/bin/cupsd -l

Nov 17 17:09:32 MathPad systemd[1]: Starting CUPS Scheduler...
Nov 17 17:09:33 MathPad systemd[1]: Started CUPS Scheduler.

@Mirdarthos

sudo grep -i name /etc/cups/cupsd.conf

This command did not return anything. Maybe the problem lies here?

[Olli]

@RiccardoP

and I manage to print test pages, but when I access any program with printing capabilities, the only printer I see is the “Save to PDF” one.

cups is active and succesful printing testpages indicates that the problem might be something else. can you check the systemsettings about the printer.

[jrichard326]

What printer are you using? Are you certain that the drivers are installed?
Is your username a member of the lp group? You can check by typing groups in terminal.
Is the printer shown when you type localhost:631 in a browser, Administration Tab-Manage-Printers. If it isn’t, can you add the printer through the browser interface?

[RiccardoP]

Thank you all for your replies.

I am in the lp group, and I can see my printer in the Manage printers tab of the CUPS manager.
I also believe that the drivers are installed. The printer is an HP Laserjet Pro 4003, and CUPS shows the corresponding Postscript driver.

I really do not know where the problem may lie. I will try to experiment a bit more today

[Kobold]

@RiccardoP

I am in the lp group, and I can see my printer in the Manage printers tab of the CUPS manager.

Im not sure which DE you are using, but in KDE I would remove this Printer in System Settings>Printer and connect your device again for a simple reinstall.

Edit:
If this not help, my next step for a workaround, i would use a older (but working) lifeboot and print from there (just disable network access when possible for security reason).