The Linux Printing Usage HOWTO

1.  Introduction

  This document describes how to use the line printer spooling system
  provided with the Linux operating system.  This HOWTO is the
  supplementary document to the Linux Printing Setup HOWTO, which
  discusses the installation and setup of the Linux printing system.
  The material presented in this HOWTO should be equally relevent for
  all flavors of the BSD operating system in addition to the Linux
  operating system.


  1.1.  Linux Printing HOWTO History

  Note from Mark Komarinski <markk@auratek.com>:

  I'd like to thank Matt Foster for doing a lot of work in the re-write
  of this HOWTO.  I'm keeping his style, and adding when necessary to
  keep everything updated.

  Note from Matt Foster <mwf@engr.uark.edu>:

  This version of the Linux Printing HOWTO is a complete rewrite of the
  one originally written by Grant Taylor <grant@god.tufts.edu> and Brian
  McCauley <B.A.McCauley@bham.ac.uk>.  I have tried to keep with the
  coverage of material presented by Grant and Brian's HOWTO, but I have
  drastically modified the style of presentation and the depth of
  material covered.  I feel that this makes the HOWTO more complete and
  easier to read.  I can only hope that you agree.


  1.2.  Version History

  v1.2.2

  o  Re-indexed, other changes to fit in the new RedHat docs.  Thanks
     Ed!

     v1.2.1

  o  updates, some changes for Dr. Linux publication

     v1.2

  o  Windows Printers

  o  Changing max size of print files

     v1.11

  o  new maintainter!

  o  Added lpc info

  o  Added some info for troubleshooting

  o  A start on printing graphics files!

  v1.1

  o  revised some of the wording


  o  developed section on PostScript printing

  o  attempted to clarify some of the examples 8-)

  o  fleshed the discussion of the basic Linux printing utilities

  v1.0

  o  initial public release of the Printing Usage HOWTO


  1.3.  Copyrights and Trademarks

  Some names mentioned in this HOWTO are claimed as copyrights and/or
  trademarks of certain persons and/or companies.  These names appear in
  full or initial caps in this HOWTO.

  (c) 1995 Matt Foster (mwf@engr.uark.edu)
  (c) 1996-1997 Mark F. Komarinski (markk@auratek.com)

  All translations, derivative works, or aggregate works incorporating
  any Linux HOWTO documents must be covered under this copyright notice.

  That is, you may not produce a derivative work from a HOWTO and impose
  additional restrictions on its distribution. Exceptions to these rules
  may be granted under certain conditions; please contact the Linux
  HOWTO coordinator at the address given below.

  In short, we wish to promote dissemination of this information through
  as many channels as possible. However, we do wish to retain copyright
  on the HOWTO documents, and would like to be notified of any plans to
  redistribute the HOWTOs.


  If you have questions, please contact Tim Bynum, the Linux HOWTO
  coordinator, at <linux-howto@sunsite.unc.edu>. You may finger this
  address for phone number and additional contact information.



  1.4.  Downloading the Linux Printing HOWTOs

  I recommend that if you want to print a copy of this HOWTO that you
  download the PostScript version.  It is formatted in a fashion that is
  aesthetically appealing and easier to read.  You can get the
  PostScript version from one of the many Linux distribution sites (such
  as SunSITE <ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/>).


  1.5.  Feedback

  Questions, comments, or corrections for this HOWTO may be directed to
  <markk@auratek.com>.


  1.6.  Acknowledgments

  Thanks go out to all of the people who took the time to read the alpha
  version of this HOWTO and respond with many helpful comments and
  suggestions---some of you may see your comments reflected in the
  version.

  I'd also like to thank Matt Foster who did the original re-write.



  2.  Printing Under Linux

  This section discusses how to print files, examine the print queue,
  remove jobs from the print queue, format files before printing them,
  and configure your printing environment.


  2.1.  History of Linux Printing

  The Linux printing system---the lp system---is a port of the source
  code written by the Regents of the University of California for the
  Berkeley Software Distribution version of the UNIX operating system.


  2.2.  Printing a File Using lpr

  By far, the most simplistic way to print in the Linux operating system
  is to send the file to be printed directly to the printing device.
  One way to do this is to use the cat command.  As the root user, one
  could do something like



       # cat thesis.txt > /dev/lp



  In this case, /dev/lp is a symbolic link to the actual printing
  device---be it a dot-matrix, laser printer, typesetter, or plotter.
  (See ln(1) for more information on symbolic links.)

  For the purpose of security, only the root user and users in the same
  group as the print daemon are able to write directly to the printer.
  This is why commands such as lpr, lprm, and lpq have to be used to
  access the printer.

  Because of this, users have to use lpr to print a file.  The lpr
  command takes care of all the initial work needed to print the file,
  and then it hands control over to another program, lpd, the line
  printing daemon.  The line printing daemon then tells the printer how
  to print the file.

  When lpr is executed, it first copies the specified file to a certain
  directory (the spool directory) where the file remains until lpd
  prints it.  Once lpd is told that there is a file to print, it will
  spawn a copy of itself (what we programmers call forking).  This copy
  will print our file while the original copy waits for more requests.
  This allows for multiple jobs to be queued at once.

  The syntax of lpr(1) is a very familiar one,



       $ lpr [ options ] [ filename ... ]



  If filename is not specified, lpr expects input to come from standard
  input (usually the keyboard, or another program's output).  This
  enables the user to redirect a command's output to the print spooler.
  As such,



  $ cat thesis.txt | lpr



  or,



       $ pr -l60 thesis.txt | lpr



  The lpr command accepts several command-line arguments that allow a
  user to control how it works.  Some of the most widely used arguments
  are: -Pprinter specifies the printer to use, -h suppresses printing of
  the burst page, -s creates a symbolic link instead of copying the file
  to the spool directory (useful for large files), and -#num specifies
  the number of copies to print.  An example interaction with lpr might
  be something like



       $ lpr -#2 -sP dj thesis.txt



  This command will create a symbolic link to the file thesis.txt in the
  spool directory for the printer named dj, where it would be processed
  by lpd.  It would then print a second copy of thesis.txt.

  For a listing of all the options that lpr will recognize, see lpr(1).


  2.3.  Viewing the Print Queue with lpq

  To view the contents of the print queue, use the lpq command.  Issued
  without arguments, it returns the contents of the default printer's
  queue.

  The returned output of lpq can be useful for many purposes.



       $ lpq
       lp is ready and printing
       Rank   Owner      Job  Files                            Total Size
       active mwf        31   thesis.txt                       682048 bytes



  2.4.  Canceling a Print Job Using lprm

  Another useful feature of any printing system is the ability to cancel
  a job that has been previously queued.  To do this, use lprm.



       $ lprm -



  The above command cancels all of the print jobs that are owned by the
  user who issued the command.  A single print job can be canceled by
  first getting the job number as reported by lpq and then giving that
  number to lprm.  For example,



       $ lprm 31



  would cancel job 31 (thesis.txt) on the default printer.


  2.5.  Controlling the lpd program with lpc

  The lpc(8) program is used to control the printers that lpd serves.
  you can enable or disable a printer or its queues, rearrange entries
  within a queue, and get a status report on the printers and their
  queues.  Lpc is mostly used in a setup where there are multiple
  printers hanging off one machine.



       $ lpc



  The above will start the lpc program.  By default, this enters you
  into an interactive mode, and you can begin issuing commands.  The
  other option is to issue an lpc command on the command line.



       $ lpc status all



  A list of the available commands are in the lpd man page, but here are
  a few of the major commands you'll want to know about.  Any commands
  marked with option can either be a printer name (lp, print, etc) or
  the keyword all, which means all printers.


  o  disable option -  prevents any new printer job from being entered

  o  down option - disables all printing on the printer

  o  enable option - allow new jobs to enter the print queue

  o  quit (or exit) - leave lpc

  o  restart option - restarts lpd for that printer

  o  status option - print status of printer

  o  up option - enable everything and start a new lpd


  2.6.  The RedHat printtool

  Just a quick note here on RedHat's amazing printtool program.  It
  seems to do everything that a magicfilter would do.  RedHat already
  installs many of the programs to do the filtering.  Here's how I have
  my printer set up under RH 4.0 with an HP LJ 4L connected to my
  parallel port (should be the same for other versions of RH as well).

  o  Become root and fire up printtool (if you su'ed, you remembered to
     SETENV DISPLAY :0.0 and xhost +, right?)

  o  Click "Add", and hit "OK" for a local printer.

  o  Fill in the printer device (/dev/lp1 for me)

  o  Fill in the input filter - Select a printer type, resolution, and
     paper size (ljet4, 300x300, and letter)

  o  Hit "OK" all the way back, and restart the lpd.

     Just like rolling an /etc/printcap file by hand, you can have
     multiple printer definitions for each physical printer.  One for
     different paper sizes, resolutions, etc.


  3.  Printing files

  This section covers printing the kinda of files that you'll run across
  in a Linux setup.


  3.1.  Printing graphics files

  Printing graphics files through a printer usually depends on the kind
  of graphics you're converting, and the kind of printer you want to
  send to. Dot matrix is usually out of the question due to differences
  in the way dot-matrix handles graphics.  Your best bet in this
  situation is to see if your printer is compatable with an Epson or an
  IBM ProPrinter, then convert the graphics file to PostScript, then use
  Ghostscript (see next section) to print the graphics.

  If you have a laser printer, things are a bit easier since many are
  compatable with PCL.  This now gives you a few options.  Some programs
  may output directly in PCL.  If not, programs like NetPBM can convert
  into PCL.  Last option is to use ghostscript (see next section).

  Your absolutely best option is to install packages like NetPBM and
  Ghostscript then installing a magic filter to process the graphics
  files automagically.


  3.2.  Printing PostScript files

  Printing PostScript files on a printer that has a PostScript
  interpreter is simple; just use lpr, and the printer will take care of
  all of the details for you.  For those of us that don't have printers
  with PostScript capabilities, we have to resort to other means.
  Luckily, there are programs available that can make sense of
  PostScript, and translate it into a language that most printers will
  understand.  Probably the most well known of these programs is
  Ghostscript.

  Ghostscript's responsibility is to convert all of the descriptions in
  a PostScript file to commands that the printer will understand.  To
  print a PostScript file using Ghostscript, you might do something like



       $ gs -dSAFER -dNOPAUSE -sDEVICE=deskjet -sOutputFile=\|lpr thesis.ps

  Notice in the above example that we are actually piping the output of
  Ghostscript to the lpr command by using the -sOutputFile option.

  Ghostview is an interface to Ghostscript for the X Window System.  It
  allows you to preview a PostScript file before you print it.
  Ghostview and Ghostscript can both be swiped from
  <ftp://prep.ai.mit.edu/pub/gnu/>.


  3.3.  Printing PDF files

  Adobe has released an Acrobat reader for Linux, and it's available on
  the Adobe home page  <http://www.adobe.com>.  Its predecessor, xpdf,
  is also available.  Both should print to a postscript device.


  3.4.  Printing TeX files

  One of the easiest ways to print TeX files is to convert them to
  PostScript and then print them using Ghostscript.  To do this, you
  first need to convert them from TeX to a format known as DVI (which
  stands for device-independent). You can do this with the tex(1)
  command.  Then you need to convert the DVI file to a PostScript file
  using dvips.  All of this would look like the following when typed in.



       $ tex thesis.tex
       $ dvips thesis.dvi



  Now you are ready to print the resulting PostScript file as described
  above.


  3.5.  Printing troff  formatted files



       $ groff -Tascii thesis.tr | lpr



  or, if you prefer,



       $ groff thesis.tr > thesis.ps



  and then print the PostScript file as described above.


  3.6.  Printing man  pages



       $ man man | col -b | lpr

  The man pages contain pre-formatted troff data, so we have to strip
  out any highlighting, underlines, etc.  The 'col' program does this
  just nicely, and since we're piping data, the man program won`t use
  more.

  4.  Miscellaneous Items

  This covers topics not in any of the others.


  4.1.  Formatting Before Printing

  Since most ASCII files are not formatted for printing, it is useful to
  format them in some way before they are actually printed.  This may
  include putting a title and page number on each page, setting the
  margins, double spacing, indenting, or printing a file in multiple
  columns.  A common way to do this is to use a print preprocessor such
  as pr.



       $ pr +4 -d -h"Ph.D. Thesis, 2nd Draft" -l60 thesis.txt | lpr



  In the above example, pr would take the file thesis.txt and skip the
  first three pages (+4), set the page length to sixty lines (-l60),
  double space the output (-d), and add the phrase "Ph.D. Thesis, 2nd
  Draft" to the top of each page (-h).  Lpr would then queue pr's
  output.  See its on-line manual page for more information on using pr.


  4.2.  The PRINTER Environment Variables

  All of the commands in the Linux printing system accept the -P option.
  This option allows the user to specify which printer to use for
  output.  If a user doesn't specify which printer to use, then the
  default printer will be assumed as the output device.

  Instead of having to specify a printer to use every time that you
  print, you can set the PRINTER environment variable to the name of the
  printer that you want to use.  This is accomplished in different ways
  for each shell.  For bash you can do this with



       $ PRINTER="printer_name"; export PRINTER



  and csh, you can do it with



       % setenv PRINTER "printer_name"



  These commands can be placed in your login scripts (.profile for bash,
  or .cshrc for csh), or issued on the command-line.  (See bash(1) and
  csh(1) for more information on environment variables.)


  5.  Answers to Frequently Asked Questions


  Q1.  How do I prevent the staircase effect?

  A1.  The staircase effect is caused by the way some printers expect
  lines to be terminated.  Some printers want lines that end with a
  carriage-return/line-feed sequence (DOS-style) instead of the line-
  feed sequence used for UNIX-type systems.  The easiest way to fix this
  is to see if your printer can switch between the two styles
  somehow---either by flipping a DIP switch, or by sending an escape
  sequence at the start of each print job.  To do the latter, you need
  to create a filter (see Q2).

  A quick fix is to use a filter on the command-line.  An example of
  this might be



       $ cat thesis.txt | todos | lpr



  Q2.  What is a filter?

  A2.  A filter is a program that reads from standard input (stdin),
  performs some action on this input, and writes to standard output
  (stdout).  Filters are used for a lot of things, including text
  processing.


  Q3.  What is a magic filter?

  A3.  A magic filter is a filter that performs an action based on a
  file's type.  For example, if the file is a plain, text file, it would
  simply print the file using the normal methods.  If the file is a
  PostScript file, or any other format, it would print it using another
  method (ghostscript).  Two examples of this is magicfilter and
  APSfilter.  One caveat of these filters is that the appropriate
  programs have to be installed before you install the filter.

  The reason for this is that when the magicfilter gets installed, it
  queries your system for specific programs (such as ghostscript - if it
  finds it, then it knows it can handle PostScript data), then builds
  itself based on what it finds.  To handle all the printer files, you
  should probably have at least the following installed:

  o  GhostScript

  o  TeX

  o  NetPBM

  o  jpeg utilities

  o  gzip


  Q4.  What about the Windows Printing System?  Will Linux work with
  that?

  A4.  Maybe.  Printers that accept only the WPS commands will not work
  with Linux.  Printers that accept WPS and other commands (such as the
  Canon BJC 610) will work, as long as they're set to something other
  than WPS format.  Other printers, such as some HP DeskJet 820Cxi/Cse,
  will *not* work with Linux.  That being said, Linux can act as a print
  server (See Samba) for Win95 machines, since Win95 has drivers for
  those printers.


  Q5.  What kinda cheey system is this?  I can't print more than 6 pages
  or else I get a "file too large" error.

  A5.  One of the options in the /etc/printcap file relates to the
  maximum size of a print file.  The default is 1000 disk blocks (about
  500k?).  For PostScript files and the like, this will give you maybe
  6-8 pages with graphics and all.  Be sure to add the following line in
  the printer definition:


       mx=0



  The primary reason for this is to keep the spool partition from get-
  ting filled.  There is another way to do it, by making lpr create a
  soft link from the spool directory to your print file.  But you have
  to remember to add the -s option to lpr every time.


  6.  Troubleshooting

  This section covers some common things that can go wrong with your
  printing system.

  If your printer doesn't work:

  o  Do other print jobs work? (application problem?)

  o  Is lpd running? (check it using lpc) (print controller?)

  o  Can root send something directly to the printer? (print services?)

  o  Can you print from DOS? (cable/printer problem?)

     Answering these questions can help find a solution.

  Send other suggestions for this section to <markk@auratek.com>.


  7.  References

  This is a section of references on the Linux printing system.  I have
  tried to keep the references section of this HOWTO as focused as
  possible.  If you feel that I have forgotten a significant reference
  work, please do not hesitate to contact me.

  Before you post your question to a USENET group, consider the
  following:

  o  Is the printer accepting jobs?  (Use lpc(8) to verify.)

  o  Is the answer to your question covered in this HOWTO or Grant
     Taylor's Printing HOWTO?

  If any of the above are true, you may want to think twice before you
  post your question.  And, when you do finally post to a newsgroup, try
  to include pertinent information.  Try not to just say something like,
  "I'm having trouble with lpr, please help." These types of posts will
  most definitely be ignored by many.  Also try to include the kernel
  version that you're running, how the error occured, and, if any, the
  specific error message that the system returned.


     On-Line Manual Pages

     o  cat(1)  concatenate and print files

     o  dvips(1)  convert a TeX DVI file to PostScript

     o  ghostview(1)  view PostScript documents using Ghostscript

     o  groff(1)  front-end for the groff document formatting system

     o  gs(1)  Ghostscript interpreter/viewer

     o  lpc(8)  line printer control program

     o  lpd(8)  line printer spooler daemon

     o  lpq(1)  spool queue examination program

     o  lpr(1)  off-line printer

     o  lprm(1)  remove jobs from the line printer spooling queue

     o  pr(1)  convert text files for printing

     o  tex(1)  text formatting and typesetting


     USENET newsgroups

     o  comp.os.linux.*  a plethora of information on Linux

     o  comp.unix.*  discussions relating to the UNIX operating system