Provided by: cups_2.4.2-1ubuntu2_amd64 bug


       cups - a standards-based, open source printing system


       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.

       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.

       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  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.

       The  OpenPrinting  CUPS  web site ( 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.


       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:

            Whether to allow any X.509 certificate root (Y or N).

            The directory where semi-persistent cache files can be found.

            The directory where data files can be found.

            The default level of encryption (Always, IfRequested, Never, Required).

            Whether to allow expired X.509 certificates (Y or N).

            The Kerberos service name used for authentication.

            The hostname/IP address and port number  of  the  CUPS  scheduler  (hostname:port  or

            The directory where server helper programs, filters, backend, etc. can be found.

            The root directory of the server.

            The directory where state files can be found.

            Specifies the name of the user for print requests.

       HOME Specifies the home directory of the current user.

            Specifies the default port number for IPP requests.

            Specifies the location of localization files.

            Specifies the default print queue (System V standard).

            Specifies the default print queue (Berkeley standard).

            Specifies the location of temporary files.




       CUPS  conforms  to  the Internet Printing Protocol version 2.1 and implements the Berkeley
       and System V UNIX print commands.


       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).


       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
       (,    PWG   Internet   Printing   Protocol   Workgroup


       Copyright © 2021-2022 by OpenPrinting.