cups(1) 2021-02-28 cups(1)
OpenPrinting OpenPrinting
CUPS
NAME
cups - a standards-based, open source printing system
DESCRIPTION
CUPS is the software you use to print from applications like word
processors, email readers, photo editors, and web browsers. It
converts the page descriptions produced by your application (put a
paragraph here, draw a line there, and so forth) into something your
printer can understand and then sends the information to the printer
for printing. Now, since every printer manufacturer does things
differently, printing can be very complicated. CUPS does its best to
hide this from you and your application so that you can concentrate on
printing and less on how to print. Generally, the only time you need
to know anything about your printer is when you use it for the first
time, and even then CUPS can often figure things out on its own.
HOW DOES IT WORK?
The first time you print to a printer, CUPS creates a queue to keep
track of the current status of the printer (everything OK, out of
paper, etc.) and any pages you have printed. Most of the time the
queue points to a printer connected directly to your computer via a
USB port, however it can also point to a printer on your network, a
printer on the Internet, or multiple printers depending on the
configuration. Regardless of where the queue points, it will look like
any other printer to you and your applications. Every time you print
something, CUPS creates a job which contains the queue you are sending
the print to, the name of the document you are printing, and the page
descriptions. Job are numbered (queue-1, queue-2, and so forth) so you
can monitor the job as it is printed or cancel it if you see a
mistake. When CUPS gets a job for printing, it determines the best
programs (filters, printer drivers, port monitors, and backends) to
convert the pages into a printable format and then runs them to
actually print the job. When the print job is completely printed,
CUPS removes the job from the queue and moves on to any other jobs you
have submitted. You can also be notified when the job is finished, or
if there are any errors during printing, in several different ways.
WHERE DO I BEGIN?
The easiest way to start is by using the web interface to configure
your printer. Go to "http://localhost:631" and choose the
Administration tab at the top of the page. Click/press on the Add
Printer button and follow the prompts. When you are asked for a
username and password, enter your login username and password or the
"root" username and password. After the printer is added you will be
asked to set the default printer options (paper size, output mode,
etc.) for the printer. Make any changes as needed and then click/press
on the Set Default Options button to save them. Some printers also
support auto-configuration - click/press on the Query Printer for
Default Options button to update the options automatically. Once you
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CUPS
have added the printer, you can print to it from any application. You
can also choose Print Test Page from the maintenance menu to print a
simple test page and verify that everything is working properly. You
can also use the lpadmin(8) and lpinfo(8) commands to add printers to
CUPS. Additionally, your operating system may include graphical user
interfaces or automatically create printer queues when you connect a
printer to your computer.
HOW DO I GET HELP?
The OpenPrinting CUPS website (https://openprinting.github.io/cups)
provides access to the cups and cups-devel mailing lists, additional
documentation and resources, and a bug report database. Most vendors
also provide online discussion forums to ask printing questions for
your operating system of choice.
ENVIRONMENT
CUPS commands use the following environment variables to override the
default locations of files and so forth. For security reasons, these
environment variables are ignored for setuid programs:
CUPS_ANYROOT
Whether to allow any X.509 certificate root (Y or N).
CUPS_CACHEDIR
The directory where semi-persistent cache files can be found.
CUPS_DATADIR
The directory where data files can be found.
CUPS_ENCRYPTION
The default level of encryption (Always, IfRequested, Never,
Required).
CUPS_EXPIREDCERTS
Whether to allow expired X.509 certificates (Y or N).
CUPS_GSSSERVICENAME
The Kerberos service name used for authentication.
CUPS_SERVER
The hostname/IP address and port number of the CUPS scheduler
(hostname:port or ipaddress:port).
CUPS_SERVERBIN
The directory where server helper programs, filters, backend,
etc. can be found.
CUPS_SERVERROOT
The root directory of the server.
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CUPS
CUPS_STATEDIR
The directory where state files can be found.
CUPS_USER
Specifies the name of the user for print requests.
HOME Specifies the home directory of the current user.
IPP_PORT
Specifies the default port number for IPP requests.
LOCALEDIR
Specifies the location of localization files.
LPDEST
Specifies the default print queue (System V standard).
PRINTER
Specifies the default print queue (Berkeley standard).
TMPDIR
Specifies the location of temporary files.
FILES
~/.cups/client.conf
~/.cups/lpoptions
CONFORMING TO
CUPS conforms to the Internet Printing Protocol version 2.1 and
implements the Berkeley and System V UNIX print commands.
NOTES
CUPS printer drivers, backends, and PPD files are deprecated and will
no longer be supported in a future feature release of CUPS. Printers
that do not support IPP can be supported using applications such as
ippeveprinter(1).
SEE ALSO
cancel(1), client.conf(5), cupsctl(8), cupsd(8), lp(1), lpadmin(8),
lpinfo(8), lpoptions(1), lpr(1), lprm(1), lpq(1), lpstat(1), CUPS
Online Help (http://localhost:631/help), OpenPrinting CUPS Web Site
(https://openprinting.github.io/cups), PWG Internet Printing Protocol
Workgroup (http://www.pwg.org/ipp)
COPYRIGHT
Copyright [co] 2020-2024 by OpenPrinting.
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