1cups(1) OpenPrinting cups(1)
2
6 cups - a standards-based, open source printing system
7
9 CUPS is the software you use to print from applications like word pro‐
10 cessors, email readers, photo editors, and web browsers. It converts
11 the page descriptions produced by your application (put a paragraph
12 here, draw a line there, and so forth) into something your printer can
13 understand and then sends the information to the printer for printing.
14 Now, since every printer manufacturer does things differently, printing
16 can be very complicated. CUPS does its best to hide this from you and
17 your application so that you can concentrate on printing and less on
18 how to print. Generally, the only time you need to know anything about
19 your printer is when you use it for the first time, and even then CUPS
20 can often figure things out on its own.
21 HOW DOES IT WORK?
23 The first time you print to a printer, CUPS creates a queue to keep
24 track of the current status of the printer (everything OK, out of pa‐
25 per, etc.) and any pages you have printed. Most of the time the queue
26 points to a printer connected directly to your computer via a USB port,
27 however it can also point to a printer on your network, a printer on
28 the Internet, or multiple printers depending on the configuration. Re‐
29 gardless of where the queue points, it will look like any other printer
30 to you and your applications.
31 Every time you print something, CUPS creates a job which contains the
33 queue you are sending the print to, the name of the document you are
34 printing, and the page descriptions. Job are numbered (queue-1,
35 queue-2, and so forth) so you can monitor the job as it is printed or
36 cancel it if you see a mistake. When CUPS gets a job for printing, it
37 determines the best programs (filters, printer drivers, port monitors,
38 and backends) to convert the pages into a printable format and then
39 runs them to actually print the job.
40 When the print job is completely printed, CUPS removes the job from the
42 queue and moves on to any other jobs you have submitted. You can also
43 be notified when the job is finished, or if there are any errors during
44 printing, in several different ways.
45 WHERE DO I BEGIN?
47 The easiest way to start is by using the web interface to configure
48 your printer. Go to "http://localhost:631" and choose the Administra‐
49 tion tab at the top of the page. Click/press on the Add Printer button
50 and follow the prompts.
51 When you are asked for a username and password, enter your login user‐
53 name and password or the "root" username and password.
54 After the printer is added you will be asked to set the default printer
56 options (paper size, output mode, etc.) for the printer. Make any
57 changes as needed and then click/press on the Set Default Options but‐
58 ton to save them. Some printers also support auto-configuration -
59 click/press on the Query Printer for Default Options button to update
60 the options automatically.
61 Once you have added the printer, you can print to it from any applica‐
63 tion. You can also choose Print Test Page from the maintenance menu to
64 print a simple test page and verify that everything is working prop‐
65 erly.
66 You can also use the lpadmin(8) and lpinfo(8) commands to add printers
68 to CUPS. Additionally, your operating system may include graphical
69 user interfaces or automatically create printer queues when you connect
70 a printer to your computer.
71 HOW DO I GET HELP?
73 The OpenPrinting CUPS web site (https://openprinting.github.io/cups)
74 provides access to the cups and cups-devel mailing lists, additional
75 documentation and resources, and a bug report database. Most vendors
76 also provide online discussion forums to ask printing questions for
77 your operating system of choice.
78
80 CUPS commands use the following environment variables to override the
81 default locations of files and so forth. For security reasons, these
82 environment variables are ignored for setuid programs:
83 CUPS_ANYROOT
85 Whether to allow any X.509 certificate root (Y or N).
86 CUPS_CACHEDIR
88 The directory where semi-persistent cache files can be found.
89 CUPS_DATADIR
91 The directory where data files can be found.
92 CUPS_ENCRYPTION
94 The default level of encryption (Always, IfRequested, Never, Re‐
95 quired).
96 CUPS_EXPIREDCERTS
98 Whether to allow expired X.509 certificates (Y or N).
99 CUPS_GSSSERVICENAME
101 The Kerberos service name used for authentication.
102 CUPS_SERVER
104 The hostname/IP address and port number of the CUPS scheduler
105 (hostname:port or ipaddress:port).
106 CUPS_SERVERBIN
108 The directory where server helper programs, filters, backend, etc.
109 can be found.
110 CUPS_SERVERROOT
112 The root directory of the server.
113 CUPS_STATEDIR
115 The directory where state files can be found.
116 CUPS_USER
118 Specifies the name of the user for print requests.
119 HOME Specifies the home directory of the current user.
121 IPP_PORT
123 Specifies the default port number for IPP requests.
124 LOCALEDIR
126 Specifies the location of localization files.
127 LPDEST
129 Specifies the default print queue (System V standard).
130 PRINTER
132 Specifies the default print queue (Berkeley standard).
133 TMPDIR
135 Specifies the location of temporary files.
136
138 ~/.cups/client.conf
139 ~/.cups/lpoptions
140
142 CUPS conforms to the Internet Printing Protocol version 2.1 and imple‐
143 ments the Berkeley and System V UNIX print commands.
144
146 CUPS printer drivers, backends, and PPD files are deprecated and will
147 no longer be supported in a future feature release of CUPS. Printers
148 that do not support IPP can be supported using applications such as
149 ippeveprinter(1).
150
152 cancel(1), client.conf(5), cupsctl(8), cupsd(8), lp(1), lpadmin(8),
153 lpinfo(8), lpoptions(1), lpr(1), lprm(1), lpq(1), lpstat(1), CUPS On‐
154 line Help (http://localhost:631/help), OpenPrinting CUPS Web Site
155 (https://openprinting.github.io/cups), PWG Internet Printing Protocol
156 Workgroup (http://www.pwg.org/ipp)
157
159 Copyright © 2021-2022 by OpenPrinting.
1602021-02-28 CUPS cups(1)