Printing

Printing

Synopsis #

OpenBSD supports both the traditional BSD printing system (lpd) and the more feature-rich CUPS (Common UNIX Printing System). This chapter describes how to configure local and network printers, install printer drivers and filters, print to PDF, and configure an OpenBSD system as a print server.

Overview of Printing in OpenBSD #

The base system includes lpd(8), a lightweight line printer daemon that handles print spooling and basic filtering. More complex setups, such as those requiring drivers, graphical administration, or network browsing, are better handled using CUPS, which is available as a package.

Common printer types supported:

  • USB printers connected via /dev/ulpt0
  • Network printers supporting IPP, JetDirect (port 9100), or LPD
  • PostScript printers that require no additional drivers
  • Host-based printers (e.g., some HP, Samsung) via driver packages

Filters such as a2ps(1), enscript(1), and ghostscript are commonly used to prepare print jobs for printers that do not support plain text or PostScript natively.

Configuring Printing with lpd #

The lpd(8) daemon is the traditional Berkeley line printer spooler included in the OpenBSD base system. It is simple, reliable, and suitable for local or network printing where advanced features such as automatic driver detection or graphical configuration are not required. Printers must be configured manually in /etc/printcap, and format conversion (e.g., plain text to PostScript) is handled by user-supplied filters. lpd is lightweight and often preferred for small or dedicated systems.

Enabling lpd #

Enable the base printing system using rcctl:

# rcctl enable lpd
# rcctl start lpd

Ensure the printing device (such as /dev/ulpt0) is writable by the daemon user:

# chown daemon /dev/ulpt0
# chmod 600 /dev/ulpt0

Configuring /etc/printcap #

The printcap(5) file describes available printers.

Example for a local USB printer:

lp|Local USB Printer:\
    :lp=/dev/ulpt0:\
    :sd=/var/spool/output/lpd:\
    :lf=/var/log/lpd-errs:

Create and prepare the spool directory:

# mkdir -p /var/spool/output/lpd
# chown daemon:daemon /var/spool/output/lpd

To print to a remote LPD server:

remotehp:\
    :rm=192.0.2.10:\
    :rp=raw:\
    :sd=/var/spool/output/remotehp:\
    :lf=/var/log/lpd-errs:

Adding Print Filters #

If the printer does not support plain text, a print filter is required using the if= field.

Install enscript and ghostscript:

# pkg_add enscript ghostscript

Create a filter script:

# vi /usr/local/libexec/psfilter

Example content:

#!/bin/sh
exec enscript -o - | gs -q -dNOPAUSE -dBATCH -sDEVICE=ijs -sOutputFile=- - 2>/dev/null

This pipeline works as follows:

  • enscript -o - converts plain text to PostScript and sends it to standard output.

  • gs (Ghostscript) reads the PostScript input, rasterizes it using the ijs driver, and sends the output to standard output.

  • -q, -dNOPAUSE, and -dBATCH suppress prompts and exit after processing.

  • -sDEVICE=ijs selects the IJS raster output interface; alternatives include pxlmono, ljet4, and uniprint, depending on the printer.

  • -sOutputFile=- writes to standard output; 2>/dev/null suppresses errors.

This allows lpd to support a wide range of printers using external filters. Run gs -h to list supported output devices.

Make it executable:

# chmod +x /usr/local/libexec/psfilter

Update /etc/printcap:

lp:\
    :lp=/dev/ulpt0:\
    :if=/usr/local/libexec/psfilter:\
    :sd=/var/spool/output/lpd:\
    :lf=/var/log/lpd-errs:

Printing from the Command Line #

Send a job:

$ lpr file.txt

Check the queue:

$ lpq

Remove jobs:

$ lprm -

Printing with CUPS #

CUPS (Common UNIX Printing System) is a modular printing system that supports a wide range of printer protocols, drivers, and administrative tools. Unlike lpd, CUPS provides a web-based interface, automatic printer discovery, and integration with many modern printing workflows. While not part of the OpenBSD base system, it is available as a package and is recommended when using USB inkjet printers, printers requiring PPD files, or complex network printing environments.

Installing and Enabling CUPS #

Install CUPS and supporting drivers:

# pkg_add cups gutenprint foomatic-db splix hplip

Enable and start the daemon:

# rcctl enable cupsd
# rcctl start cupsd

Accessing the Web Interface #

The CUPS web interface is accessible at:

http://localhost:631

Access may require adding the user to the operator group and creating a doas rule:

permit persist :operator as root cmd /usr/local/sbin/lpadmin

Printers can be added via the web interface or with lpadmin.

Driver and Backend Support #

Check backends:

$ lpinfo -v

List available models and drivers:

$ lpinfo -m

CUPS backends support protocols such as:

  • socket:// — JetDirect
  • ipp:// or http:// — IPP printers
  • usb:// — for local printers

Printing with CUPS #

To print:

$ lp -d PRINTER file.pdf

Set the default printer:

$ lpoptions -d PRINTER

View jobs:

$ lpstat -o

Cancel a job:

$ cancel JOBID

Setting Up an OpenBSD Print Server #

lpd-Based Print Server #

Enable lpd and configure /etc/printcap with exported printers. Add trusted client hosts to /etc/hosts.lpd:

192.0.2.15
client.example.org

Client usage:

$ lpr -Pprinter@server file.txt

CUPS-Based Print Server #

Edit /etc/cups/cupsd.conf:

Listen *:631
Browsing On
BrowseLocalProtocols all
<Location />
  Order allow,deny
  Allow all
</Location>

Restart the daemon:

# rcctl restart cupsd

On client systems, configure:

/etc/cups/client.conf

with:

ServerName printserver.example.net

Clients may then use lp, lpr, or print dialogs without further configuration.

Printing to PDF #

From Graphical Applications #

Most applications that support GTK, Qt, or X11 printing dialogs allow printing to file. Select “Print to File” or “Print to PDF” and choose a destination.

Using Command-Line Tools #

Convert text to PDF using enscript and ghostscript:

$ enscript file.txt -p - | ps2pdf - output.pdf

Or use PostScript directly:

$ ps2pdf input.ps output.pdf

Virtual PDF Printer with CUPS #

Install the virtual backend:

# pkg_add cups-pdf

Add a new printer called “PDF” in the CUPS web interface. The output will be written to:

/var/spool/cups-pdf/USERNAME

The output directory can be changed in /etc/cups/cups-pdf.conf.

Remote Printing #

To a Remote lpd Server #

Use /etc/printcap:

remote:\
    :rm=printserver.example.net:\
    :rp=lp:\
    :sd=/var/spool/output/remote:\
    :lf=/var/log/lpd-errs:

To a Remote CUPS Server #

Create a configuration file:

/etc/cups/client.conf

With contents:

ServerName cups.example.net

Alternatively, set the environment variable:

$ export CUPS_SERVER=cups.example.net

Printing to Windows Shared Printers #

Install samba:

# pkg_add samba

Use a device URI like:

smb://WORKGROUP/username:password@host/sharename

CUPS can use smbspool as a backend for SMB printing. Ensure credentials are embedded if printing unattended.

Troubleshooting #

  • For lpd, check /var/log/lpd-errs
  • For CUPS, use:
$ tail -f /var/log/cups/error_log
  • Ensure printer device permissions:
# ls -l /dev/ulpt0
  • Restart the service after changes:
# rcctl restart lpd
# rcctl restart cupsd
  • For failed jobs, verify that the correct driver or filter is installed
  • Check if spool directories exist and are writable by daemon (for lpd) or the CUPS user
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