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OpenPrinting CUPS v2.4.2

Version Apache 2.0

Introduction

OpenPrinting CUPS is the most current version of CUPS, a standards-based, open source printing system for Linux® and other Unix®-like operating systems. CUPS supports printing to:

AirPrint™ and IPP Everywhere™ printers,
Network and local (USB) printers with Printer Applications, and
Network and local (USB) printers with (legacy) PPD-based printer drivers.

CUPS provides the System V ("lp") and Berkeley ("lpr") command-line interfaces, a configurable web interface, a C API, and common print filters, drivers, and backends for printing. The cups-filters project provides additional filters and drivers.

CUPS is licensed under the Apache License Version 2.0 with an exception to allow linking against GNU GPL2-only software. See the files LICENSE and NOTICE for more information.

Note: Apple maintains a separate repository for the CUPS that ships with macOS and iOS at https://github.com/apple/cups.

Reading the Documentation

Initial documentation to get you started is provided in the root directory of the CUPS sources:

CHANGES.md: A list of changes in the current major release of CUPS.
CONTRIBUTING.md: Guidelines for contributing to the CUPS project.
CREDITS.md: A list of past contributors to the CUPS project.
DEVELOPING.md: Guidelines for developing code for the CUPS project.
INSTALL.md: Instructions for building and installing CUPS.
LICENSE: The CUPS license agreement (Apache 2.0).
NOTICE: Copyright notices and exceptions to the CUPS license agreement.
README.md: This file.

Once you have installed the software you can access the documentation (and a bunch of other stuff) online at http://localhost:631/ and using the man command, for example man cups.

If you're having trouble getting that far, the documentation is located under the doc/help and man directories.

Please read the documentation before asking questions.

Getting Support and Other Resources

In addition to the OpenPrinting CUPS home page at https://openprinting.github.io/cups, we provide a mailing list for CUPS users and developers to ask questions and discuss issues at https://linuxfoundation.groups.io/g/printing.

Setting Up Printers

CUPS includes a web-based administration tool that allows you to manage printers, classes, and jobs on your server. Open http://localhost:631/admin/ in your browser to access the printer administration tools. You will be asked for the administration password (root or any other user in the "sys", "system", "root", "admin", or "lpadmin" group on your system) when performing any administrative function.

The lpadmin command is used to manage printers from the command-line. For example, the following command creates a print queue called "myprinter" for an IPP Everywhere printer at address "11.22.33.44":

lpadmin -p myprinter -E -v "ipp://11.22.33.44/ipp/print" -m everywhere

The -p option specifies the printer name. The -E option enables the printer and accepts new print jobs immediately. The -v option specifies the device URI for the printer, which tells CUPS how to communicate with the printer. And the -m option specifies the model (driver) to use, in this case the IPP Everywhere ("everywhere") driver that is used for AirPrint and IPP Everywhere printers as well as shared printers and printers supported through Printer Applications.

Legacy printers are supported using PPD (PostScript Printer Description) files that describe printer capabilities and driver programs needed for each printer. CUPS includes several sample PPD files for common legacy printers:

Driver	PPD Name
Dymo Label Printers	drv:///sample.drv/dymo.ppd
Intellitech Intellibar	drv:///sample.drv/intelbar.ppd
EPSON 9-pin Series	drv:///sample.drv/epson9.ppd
EPSON 24-pin Series	drv:///sample.drv/epson24.ppd
Generic PCL Laser Printer	drv:///sample.drv/generpcl.ppd
Generic PostScript Printer	drv:///sample.drv/generic.ppd
HP DeskJet Series	drv:///sample.drv/deskjet.ppd
HP LaserJet Series	drv:///sample.drv/laserjet.ppd
OKIDATA 9-Pin Series	drv:///sample.drv/okidata9.ppd
OKIDATA 24-Pin Series	drv:///sample.drv/okidat24.ppd
Zebra CPCL Label Printer	drv:///sample.drv/zebracpl.ppd
Zebra EPL1 Label Printer	drv:///sample.drv/zebraep1.ppd
Zebra EPL2 Label Printer	drv:///sample.drv/zebraep2.ppd
Zebra ZPL Label Printer	drv:///sample.drv/zebra.ppd

The sample drivers provide basic printing capabilities, but generally do not exercise the full potential of the printers or CUPS. Other drivers provide greater printing capabilities.

You can run the lpinfo -m command to list all of the available drivers:

lpinfo -m

Similarly, the lpinfo -v command lists the available printers and their device URIs:

lpinfo -v

Once you know the device URI and driver name, add the printer using the lpadmin command:

lpadmin -p PRINTER-NAME -E -v "DEVICE-URI" -m DRIVER-NAME

Printing Files

CUPS provides both the System V lp and Berkeley lpr commands for printing:

lp FILENAME
lpr FILENAME

Both the lp and lpr commands support printing options:

lp -o media=A4 -o resolution=600dpi FILENAME
lpr -o media=A4 -o resolution=600dpi FILENAME

CUPS recognizes many types of images files as well as PDF, PostScript, and text files, so you can print those files directly rather than through an application.

If you have an application that generates output specifically for your printer then you need to use the -oraw or -l options:

lp -o raw FILENAME
lpr -l FILENAME

This will prevent the filters from misinterpreting your print file.

Legal Stuff

CUPS is provided under the terms of the Apache License, Version 2.0 with exceptions for GPL2/LGPL2 software. A copy of this license can be found in the file LICENSE. Additional legal information is provided in the file NOTICE.

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.