CUPS Software Users Manual
CUPS-SUM-1.1.19
Easy Software Products
Copyright 1997-2003, All Rights Reserved
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This software users manual describes how to use the Common UNIX Printing SystemTM ("CUPSTM") Version 1.1.19.
CUPS provides a portable printing layer for UNIX®-based operating systems. It has been developed by Easy Software Products to promote a standard printing solution for all UNIX vendors and users. CUPS provides the System V and Berkeley command-line interfaces.
CUPS uses the Internet Printing Protocol ("IPP") as the basis for managing print jobs and queues. The Line Printer Daemon ("LPD") Server Message Block ("SMB"), and AppSocket (a.k.a. JetDirect) protocols are also supported with reduced functionality. CUPS adds network printer browsing and PostScript Printer Description ("PPD") based printing options to support real-world printing under UNIX.
CUPS includes an image file RIP that supports printing of image files to non-PostScript printers. A customized version of GNU Ghostscript 7.05 for CUPS called ESP Ghostscript is available separately to support printing of PostScript files within the CUPS driver framework. Sample drivers for Dymo, EPSON, HP, and OKIDATA printers are included that use these filters.
Drivers for thousands of printers are provided with our ESP Print Pro software, available at:
http://www.easysw.com/printpro/
CUPS is licensed under the GNU General Public License and GNU Library General Public License. Please contact Easy Software Products for commercial support and "binary distribution" rights.
This software users manual is organized into the following sections:
Various font and syntax conventions are used in this guide. Examples and their meanings and uses are explained below:
| Example | Description | |
|---|---|---|
lpstat
lpstat(1) | The names of commands; the first mention of a command or function in a chapter is followed by a manual page section number. | |
| /var
/usr/share/cups/data/testprint.ps | File and directory names. | |
| Request ID is Printer-123 | Screen output. | |
| lp -d printer filename ENTER | Literal user input; special keys like ENTER are in ALL CAPS. | |
| 12.3 | Numbers in the text are written using the period (.) to indicate the decimal point. |
This chapter provides an overview of how the Common UNIX Printing System works.
For years the printing problem has plagued UNIX. Unlike Microsoft® Windows® or Mac OS, UNIX has no standard interface or system in place for supporting printers. Among the solutions currently available, the Berkeley and System V printing systems are the most prevalent.
These printing systems support line printers (text only) or PostScript printers (text and graphics), and with some coaxing they can be made to support a full range of printers and file formats. However, because each varient of the UNIX operating system uses a different printing system than the next developing printer drivers for a wide range of printers and operating systems is extremely difficult. That combined with the limited volume of customers for each UNIX varient has forced most printer vendors to give up supporting UNIX entirely.
CUPS is designed to eliminate the printing problem. One common printing system can be used by all UNIX varients to support the printing needs of users. Printer vendors can use its modular filter interface to develop a single driver program that supports a wide range of file formats with little or no effort. Since CUPS provides both the System V and Berkeley printing commands, users (and applications) can reap the benefits of this new technology with no changes.
CUPS is based upon an emerging Internet standard called the Internet Printing Protocol. IPP has been embraced by dozens of printer and printer server manufacturers and is supported by Microsoft Windows 2000.
IPP defines a standard protocol for printing as well as managing print jobs and printer options like media size, resolution, and so forth. Like all IP-based protocols, IPP can be used locally or over the Internet to printers hundreds or thousands of miles away. Unlike other protocols, however, IPP also supports access control, authentication, and encryption, making it a much more capable and secure printing solution than older ones.
IPP is layered on top of the Hyper-Text Transport Protocol ("HTTP") which is the basis of web servers on the Internet. This allows users to view documentation, check status information on a printer or server, and manage their printers, classes, and jobs using their web browser.
CUPS provides a complete IPP/1.1 based printing system that provides Basic, Digest, and local certificate authentication and user, domain, or IP-based access control. TLS encryption will be available in future versions of CUPS.
Each file or set of files that is submitted for printing is called a job. Jobs are identified by a unique number starting at 1 and are assigned to a particular destination, usually a printer. Jobs can also have options associated with them such as media size, number of copies, and priority.
CUPS supports collections of printers known as classes. Jobs sent to a class are forwarded to the first available printer in the class.
Filters allow a user or application to print many types of files without extra effort. Print jobs sent to a CUPS server are filtered before sending them to a printer. Some filters convert job files to different formats that the printer can understand. Others perform page selection and ordering tasks.
CUPS provides filters for printing many types of image files, HP-GL/2 files, PDF files, and text files. CUPS also supplies PostScript and image file Raster Image Processor ("RIP") filters that convert PostScript or image files into bitmaps that can be sent to a raster printer.
Backends perform the most important task of all - they send the filtered print data to the printer.
CUPS provides backends for printing over parallel, serial, and USB ports, and over the network via the IPP, JetDirect (AppSocket), and Line Printer Daemon ("LPD") protocols. Additional backends are available in network service packages such as the SMB backend included with the popular SAMBA software.
Backends are also used to determine the available devices. On startup each backend is asked for a list of devices it supports, and any information that is available. This allows the parallel backend to tell CUPS that an EPSON Stylus Color 600 printer is attached to parallel port 1, for example.
Printer drivers in CUPS consist of one of more filters specific to a printer. CUPS includes sample printer drivers for Hewlett-Packard LaserJet and DeskJet printers and EPSON 9-pin, 24-pin, Stylus Color, and Stylus Photo printers. While these drivers do not generate optimal output for the different printer models, they do provide basic printing and demonstrate how you can write your own printer drivers and incorporate them into CUPS.
Printers and classes on the local system are automatically shared with other systems on the network. This allows you to setup one system to print to a printer and use this system as a printer server or spool host for all of the others. Users may then select a local printer by name or a remote printer using "name@server".
CUPS also provides implicit classes, which are collections of printers and/or classes with the same name. This allows you to setup multiple servers pointing to the same physical network printer, for example, so that you aren't relying on a single system for printing. Because this also works with printer classes, you can setup multiple servers and printers and never worry about a single point of failure unless all of the printers and servers go down!
This chapter shows you how to submit, query, and cancel print jobs to different printers.
CUPS provides both the System V (lp(1)) and Berkeley (
lpr(1)) printing commands. Type the following command to print a
file to the default (or only) printer on the system:
lp filename ENTER
or:
lpr filename ENTER
CUPS understands many different types of files directly, including PostScript and image files. This allows you to print from inside your applications or at the command-line, whichever is most convenient!
Many systems will have more than one printer available to the user. These printers can be attached to the local system via a parallel, serial, or USB port, or available over the network.
Use the lpstat(1) command to see a list of available
printers:
lpstat -p -d ENTER
The -p option specifies that you want to see a list of
printers, and the -d option reports the current default
printer or class.
Use the -d option with the lp command to
print to a specific printer:
lp -d printer filename ENTER
or the -P option with the lpr command:
lpr -P printer filename ENTER
For many types of files, the default printer options may be sufficient for your needs. However, there may be times when you need to change the options for a particular file you are printing.
The lp and lpr commands allow you to pass
printer options using the -o option:
lp -o landscape -o scaling=75 -o media=A4 filename.jpg lpr -o landscape -o scaling=75 -o media=A4 filename.jpg
The available printer options vary depending on the printer. The standard options are described in Chapter 3, "Standard Printing Options".
Both the lp and lpr commands have options
for printing more than one copy of a file:
lp -n num-copies filename ENTER lpr -#num-copies filename ENTER
Copies are normally not collated for you. Use the -o
Collate=True option to get collated copies :
lp -n num-copies -o Collate=True filename ENTER lpr -#num-copies -o Collate=True filename ENTER
The lpstat command can be used to check for jobs that
you have submitted for printing:
lpstat ENTER Printer-1 johndoe 4427776 Printer-2 johndoe 15786 Printer-3 johndoe 372842
The jobs are listed in the order they will be printed. Use the
-p option to see which files and printers are active:
lpstat -p ENTER printer DeskJet now printing DeskJet-1.
Use the -o and -p options together to show
the jobs and the printers:
lpstat -o -p ENTER Printer-1 johndoe 4427776 Printer-2 johndoe 15786 Printer-3 johndoe 372842 printer DeskJet now printing DeskJet-1.
Since CUPS uses the Internet Printing Protocol, it is also a fully-functional web server. To use your web browser to monitor the printers on your system, open the URL:
http://localhost:631
From there you can view the status of classes, jobs, and printers with the click of a button!
The cancel(1) and lprm(1) commands cancel a
print job:
cancel job-id ENTER lprm job-id ENTER
The job-id is the number that was reported to you by the
lp or lpstat commands.
This chapter describes the standard printer options that are
available when printing with the lp and lpr
commands.
The following options apply when printing all types of files.
The -o media=xyz option sets the media size, type,
and/or source:
lp -o media=Letter filename ENTER lp -o media=Letter,MultiPurpose filename ENTER lpr -o media=Letter,Transparency filename ENTER lpr -o media=Letter,MultiPurpose,Transparency filename ENTER
The available media sizes, types, and sources depend on the printer, but most support the following options (case is not significant):
Letter - US Letter (8.5x11 inches, or 216x279mm)Legal - US Legal (8.5x14 inches, or 216x356mm)A4 - ISO A4 (8.27x11.69 inches, or 210x297mm)COM10 - US #10 Envelope (9.5x4.125 inches, or
241x105mm)DL - ISO DL Envelope (8.66x4.33 inches, or 220x110mm)Transparency - Transparency media type or sourceUpper - Upper paper trayLower - Lower paper trayMultiPurpose - Multi-purpose paper trayLargeCapacity - Large capacity paper trayThe actual options supported are defined in the printer's PPD file in
the PageSize, InputSlot, and MediaType
options.
The -o landscape option will rotate the page 90 degrees
to print in landscape orientation:
lp -o landscape filename ENTER lpr -o landscape filename ENTER
The -o sides=two-sided-short-edge and -o
sides=two-sided-long-edge options will enable duplexing on the
printer, if the printer supports it. The -o
sides=two-sided-short-edge option is suitable for landscape
pages, while the -o sides=two-sided-long-edge option is
suitable for portrait pages:
lp -o sides=two-sided-short-edge filename ENTER lp -o sides=two-sided-long-edge filename ENTER lpr -o sides=two-sided-long-edge filename ENTER
The default is to print single-sided:
lp -o sides=one-sided filename ENTER lpr -o sides=one-sided filename ENTER
The following options apply when printing all types of files.
The -o jobsheets=start,end option sets the banner
page(s) to use for a job:
lp -o job-sheets=none filename ENTER lp -o job-sheets=standard filename ENTER lpr -o job-sheets=classified,classified filename ENTER
If only one banner file is specified, it will be printed before the files in the job. If a second banner file is specified, it is printed after the files in the job.
The available banner pages depend on the local system configuration; CUPS includes the following banner files:
none - Do not produce a banner page.classified - A banner page with a "classified" label at
the top and bottom.confidential - A banner page with a "confidential"
label at the top and bottom.secret - A banner page with a "secret" label at the top
and bottom.standard - A banner page with no label at the top and
bottom.topsecret - A banner page with a "top secret" label at
the top and bottom.unclassified - A banner page with an "unclassified"
label at the top and bottom.The following options apply when printing all types of files.
The -o page-ranges=pages option selects a range of pages
for printing:
lp -o page-ranges=1 filename ENTER lp -o page-ranges=1-4 filename ENTER lp -o page-ranges=1-4,7,9-12 filename ENTER lpr -o page-ranges=1-4,7,9-12 filename ENTER
As shown above, the pages value can be a single page, a
range of pages, or a collection of page numbers and ranges separated by
commas. The pages will always be printed in ascending order, regardless
of the order of the pages in the page-ranges option.
The default is to print all pages.
Use the -o page-set=set option to select the even or odd
pages:
lp -o page-set=odd filename ENTER lp -o page-set=even filename ENTER lpr -o page-set=even filename ENTER
The default is to print all pages.
The the -o outputorder=order option to set the output
order of all pages:
lp -o outputorder=normal filename ENTER lp -o outputorder=reverse filename ENTER lpr -o outputorder=reverse filename ENTER
The -o number-up=value option selects N-Up printing.
N-Up printing places multiple document pages on a single printed page.
CUPS supports 1, 2, 4, 6, 9, and 16-Up formats; the default format is
1-Up:
lp -o number-up=1 filename ENTER lp -o number-up=2 filename ENTER lp -o number-up=4 filename ENTER lpr -o number-up=16 filename ENTER
The -o page-border=value option chooses the border to
draw around each page:
-o page-border=double; draw two hairline borders around
each page-o page-border=double-thick; draw two 1pt borders
around each page-o page-border=none; do not draw a border (default)-o page-border=single; draw one hairline border around
each page-o page-border=single-thick; draw one 1pt border around
each pageThe -o number-up-layout=value option chooses the layout
of the pages on each output page:
-o number-up-layout=btlr; Bottom to top, left to right-o number-up-layout=btrl; Bottom to top, right to left-o number-up-layout=lrbt; Left to right, bottom to top-o number-up-layout=lrtb; Left to right, top to bottom
(default)-o number-up-layout=rlbt; Right to left, bottom to top-o number-up-layout=rltb; Right to left, top to bottom-o number-up-layout=tblr; Top to bottom, left to right-o number-up-layout=tbrl; Top to bottom, right to leftYou can mirror a print using the -o mirror option:
lp -o mirror filename ENTER lpr -o mirror filename ENTER
This is useful for printing mirrored pages on transfer paper, for T shirts, mugs, etc.
You can control the overall brightness of the printed output using
the -o brightness=percent option:
lp -o brightness=120 filename ENTER lpr -o brightness=120 filename ENTER
Values greater than 100 will lighten the print, while values less than 100 will darken it.
You can control the overall gamma correction of the printed output
using the -o gamma=value option:
lp -o gamma=1700 filename ENTER lpr -o gamma=1700 filename ENTER
Values greater than 1000 will lighten the print, while values less than 1000 will darken it. The default gamma is 1000.
The following options apply when printing text files.
The -o cpi=value option sets the number of characters
per inch:
lp -o cpi=10 filename ENTER lp -o cpi=12 filename ENTER lpr -o cpi=17 filename ENTER
The default characters per inch is 10.
The -o lpi=value option sets the number of lines per
inch:
lp -o lpi=6 filename ENTER lpr -o lpi=8 filename ENTER
The default lines per inch is 6.
The -o columns=value option sets the number of text
columns:
lp -o columns=2 filename ENTER lpr -o columns=3 filename ENTER
The default number of columns is 1.
Normally the page margins are set to the hard limits of the printer.
Use the -o page-left=value, -o page-right=value
, -o page-top=value, and -o page-bottom=value
options to adjust the page margins:
lp -o page-left=value filename ENTER lp -o page-right=value filename ENTER lp -o page-top=value filename ENTER lp -o page-bottom=value filename ENTER lpr -o page-bottom=value filename ENTER
The value argument is the margin in points; each point
is 1/72 inch or 0.35mm.
The -o prettyprint option puts a header at the top of
each page with the page number, job title (usually the filename), and
the date. Also, C and C++ keywords are highlighted, and comment lines
are italicized:
lp -o prettyprint filename ENTER lpr -o prettyprint filename ENTER
The following options apply when printing image files.
The -o position=name option specifies the position of
the image on the page:
center - Center the image on the page (default)top - Print the image centered at the top of the pageleft - Print the image centered on the left of pageright - Print the image centered on the right of the
pagetop-left - Print the image at the top left corner of
the pagetop-right - Print the image at the top right corner of
the pagebottom - Print the image centered at the bottom of the
pagebottom-left - Print the image at the bottom left corner
of the pagebottom-right - Print the image at the bottom right
corner of the pageThe -o scaling=percent, -o ppi=value, and
-o natural-scaling=percent options change the size of a printed
image:
lp -o scaling=percent filename ENTER lp -o ppi=value filename ENTER lpr -o natural-scaling=percent filename ENTER
The scaling=percent value is a number from 1 to 800
specifying the size in relation to the page (not the image.) A
scaling of 100 percent will fill the page as completely as the image
aspect ratio allows. A scaling of 200 percent will print on up to 4
pages.
The ppi=value value is a number from 1 to 1200
specifying the resolution of the image in pixels per inch. An image
that is 3000x2400 pixels will print 10x8 inches at 300 pixels per inch,
for example. If the specified resolution makes the image larger than
the page, multiple pages will be printed to satisfy the request.
The natural-scaling=percent value is a number from 1 to
800 specifying the size in relation to the natural image size. A
scaling of 100 percent will print the image at its natural size, while
a scaling of 50 percent will print the image at half its natural size.
If the specified scaling makes the image larger than the page, multiple
pages will be printed to satisfy the request.
The -o hue=value option will adjust the hue of the
printed image, much like the tint control on your television:
lp -o hue=value filename ENTER lpr -o hue=value filename ENTER
The value argument is a number from -360 to 360 and
represents the color hue rotation. The following table summarizes the
change you'll see with different colors:
| Original | hue=-45 | hue=45 |
|---|---|---|
| Red | Purple | Yellow-orange |
| Green | Yellow-green | Blue-green |
| Yellow | Orange | Green-yellow |
| Blue | Sky-blue | Purple |
| Magenta | Indigo | Crimson |
| Cyan | Blue-green | Light-navy-blue |
The default hue adjustment is 0.
The -o saturation=percent option adjusts the saturation
of the colors in an image, much like the color knob on your television:
lp -o saturation=percent filename ENTER lpr -o saturation=percent filename ENTER
The percent argument specifies the color saturation from
0 to 200. A color saturation of 0 produces a black-and-white print,
while a value of 200 will make the colors extremely intense.
The default saturation is 100.
The following options apply to HP-GL/2 files.
The -o blackplot option specifies that all pens should
plot in black:
lp -o blackplot filename ENTER lpr -o blackplot filename ENTER
The default is to use the colors defined in the plot file or the standard pen colors defined in the HP-GL/2 reference manual from Hewlett Packard.
The -o fitplot option specifies that the plot should be
scaled to fit on the page:
lp -o fitplot filename ENTER lpr -o fitplot filename ENTER
The default is to use the absolute distances specified in the plot file.
| NOTE:
This feature depends upon an accurate plot size ( |
The -o penwidth=value option specifies the default pen
width for HP-GL/2 files:
lp -o penwidth=value filename ENTER lpr -o penwidth=value filename ENTER
The pen width value specifies the pen width in
micrometers. The default value of 1000 produces lines that are 1
millimeter in width. Specifying a pen width of 0 produces lines that
are exactly 1 pixel wide.
| NOTE:
This option is ignored when the pen widths are set in the plot file. |
The -o raw option allows you to send files directly to a
printer without filtering. This is sometimes required when printing
from applications that provide their own "printer drivers" for your
printer:
lp -o raw filename ENTER lpr -o raw filename ENTER
The -l option can also be used with the lpr
command to send files directly to a printer:
lpr -l filename ENTER
This chapter describes how to save printer options for your printer and set your own default printer.
Each printer supports a large number of options, which you learned about in Chapter 3, "Standard Printer Options". Rather than specifying these options each time you print a file, CUPS allows you to save them as "default" options for the printer.
The lpoptions(1) command saves the options for your
printers. Like the lp and lpr commands, it
accepts printer options using the -o argument:
lpoptions -o prettyprint ENTER lpoptions -o media=A4 -o sides=two-sided-long-edge ENTER lpoptions -o media=Legal -o scaling=100 ENTER
Once saved, any lp or lpr command will use
them when you print.
| Note:
Running the |
The previous example shows how to set the options for the default
printer. The -p printer option specifies the options are
for another printer:
lpoptions -p laserjet -o prettyprint ENTER lpoptions -p laserjet -o media=A4 -o sides=two-sided-long-edge ENTER lpoptions -p deskjet -o media=Legal -o scaling=100 ENTER
The previous two examples shows how to set options for the default
and a specific printer. Below, shows you how to remove the saved option
using the -r argument:
lpoptions -r prettyprint ENTER lpoptions -p laserjet -r prettyprint ENTER
The lpoptions command can also be used to show the
current options by not specifying any new options on the command-line:
lpoptions ENTER media=A4 sides=two-sided-long-edge lpoptions -p deskjet ENTER media=Legal scaling=100
You can display the supported options using the lpoptions
command with the -l option, as follows:
lpoptions -p laserjet -l ENTER
The administrator normally will set a system-wide default printer
that is normally used as the default printer by everyone. Use the
-d printer option to set your own default printer:
lpoptions -d deskjet ENTER
The printer can be local (deskjet) or remote (
deskjet@server).
Besides setting options for each print queue, CUPS supports
printer instances which allow you to define several different sets
of options for each printer. You specify a printer instance using the
slash (/) character:
lpoptions -p laserjet/duplex -o sides=two-sided-long-edge ENTER lpoptions -p laserjet/legal -o media=Legal ENTER
The lp and lpr commands also understand
this notation:
lp -d laserjet/duplex filename ENTER lpr -P laserjet/legal filename ENTER
Use the -x printer/instance option to remove a printer
instance that you no longer need:
lpoptions -x laserjet ENTER lpoptions -x laserjet/duplex ENTER lpoptions -x laserjet/legal ENTER
The -x option only removes the default options for that
printer and instance; the original print queue will remain until
deleted with the lpadmin(8) command by the administrator.
Copyright 1997-2003 by Easy Software Products
44141 AIRPORT VIEW DR STE 204
HOLLYWOOD, MARYLAND 20636-3111 USA
Voice: +1.301.373.9600
Email: cups-info@cups.org
WWW: http://www.cups.org
The Common UNIX Printing SystemTM, ("CUPSTM"), is provided under the GNU General Public License ("GPL") and GNU Library General Public License ("LGPL"), Version 2, with exceptions for Apple operating systems and the OpenSSL toolkit. A copy of the exceptions and licenses follow this introduction.
The GNU LGPL applies to the CUPS API library, located in the "cups" subdirectory of the CUPS source distribution and in the "cups" include directory and library files in the binary distributions. The GNU GPL applies to the remainder of the CUPS distribution, including the "pdftops" filter which is based upon Xpdf and the CUPS imaging library.
For those not familiar with the GNU GPL, the license basically allows you to:
What this license does not allow you to do is make changes or add features to CUPS and then sell a binary distribution without source code. You must provide source for any new drivers, changes, or additions to the software, and all code must be provided under the GPL or LGPL as appropriate. The only exceptions to this are the portions of the CUPS software covered by the Apple operating system license exceptions outlined later in this license agreement.
The GNU LGPL relaxes the "link-to" restriction, allowing you to develop applications that use the CUPS API library under other licenses and/or conditions as appropriate for your application.
In addition, as the copyright holder of CUPS, Easy Software Products grants the following special exceptions:
This file is subject to the Apple OS-Developed Software exception.
No developer is required to provide these exceptions in a derived work.
Easy Software Products has trademarked the Common UNIX Printing System, CUPS, and CUPS logo. These names and logos may be used freely in any direct port or binary distribution of CUPS. Please contract Easy Software Products for written permission to use them in derivative products. Our intention is to protect the value of these trademarks and ensure that any derivative product meets the same high-quality standards as the original.
Easy Software Products also sells rights to the CUPS source code under a binary distribution license for vendors that are unable to release source code for their drivers, additions, and modifications to CUPS under the GNU GPL and LGPL. For information please contact us at the address shown above.
The Common UNIX Printing System provides a "pdftops" filter that is based on the Xpdf software. For binary distribution licensing of this software, please contact:
Derek B. Noonburg
Email: derekn@foolabs.com
WWW: http://www.foolabs.com/xpdf/
Easy Software Products sells software support for CUPS as well as a commercial printing product based on CUPS called ESP Print Pro. You can find out more at our web site:
http://www.easysw.com/
Version 2, June 1991
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