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       groff - front-end for the groff document formatting system


       [file ...]  -h | --help -v | --version [option ...]


       This  document  describes the groff program, the main front-end for the
       groff document formatting system.  The groff program and macro suite is
       the  implementation  of  a  roff(7)  system  within  the  free software
       collection GNU The groff system has all features of the classical roff,
       but adds many extensions.

       The  groff  program allows to control the whole groff system by command
       line options.  This is a great  simplification  in  comparison  to  the
       classical case (which uses pipes only).


       The  command line is parsed according to the usual GNU convention.  The
       whitespace between a command line option and its argument is  optional.
       Options  can  be  grouped  behind  a  single  ‘-’ (minus character).  A
       filename of - (minus character) denotes the standard input.

       As groff is a wrapper program for troff both programs share  a  set  of
       options.  But the groff program has some additional, native options and
       gives a new meaning to some troff options.  On the other hand, not  all
       troff options can be fed into groff.

   Native groff Options
       The  following options either do not exist for troff or are differently
       interpreted by groff.

       -D arg Set default input encoding used by preconv to arg.  Implies  -k.

       -e     Preprocess with eqn.

       -g     Preprocess with grn.

       -G     Preprocess with grap.

       -h     --help Print a help message.

       -I dir This  option  may  be  used to specify a directory to search for
              files (both those on the command line and those named  in  .psbb
              and  .so requests, and \Xps: import’ and \Xps: file’ escapes).
              The current directory is always searched first.  This option may
              be specified more than once; the directories are searched in the
              order specified.  No directory search  is  performed  for  files
              specified  using  an  absolute path.  This option implies the -s

       -k     Preprocess  with  preconv.   This  is  run  before   any   other
              preprocessor.   Please  refer  to  preconv’s manual page for its
              behaviour if no -K (or -D) option is specified.

       -K arg Set input encoding used by preconv to arg.  Implies -k.

       -l     Send the output to a spooler program for printing.  The  command
              that  should  be used for this is specified by the print command
              in the device description  file,  see  groff_font(5).   If  this
              command  is  not  present,  the  output is piped into the lpr(1)
              program by default.  See options -L and -X.

       -L arg Pass arg to the spooler program.  Several  arguments  should  be
              passed with a separate -L option each.  Note that groff does not
              prepend ‘-’ (a minus sign) to  arg  before  passing  it  to  the
              spooler program.

       -N     Don’t allow newlines within eqn delimiters.  This is the same as
              the -N option in eqn.

       -p     Preprocess with pic.

       -P -option
              -P -option -P arg  Pass  -option   or   -option   arg   to   the
              postprocessor.   The option must be specified with the necessary
              preceding minus sign(s) ‘-’  or  ‘--’  because  groff  does  not
              prepend  any dashes before passing it to the postprocessor.  For
              example, to pass a title to  the  gxditview  postprocessor,  the
              shell command

                     groff -X -P -title -P ’groff it’ foo

              is equivalent to

                     groff -X -Z foo | gxditview -title ’groff it’ -

       -R     Preprocess  with  refer.   No  mechanism is provided for passing
              arguments to refer because most refer  options  have  equivalent
              language  elements  that  can  be specified within the document.
              See refer(1) for more details.

       -s     Preprocess with soelim.

       -S     Safer mode.  Pass the -S option to pic and disable the following
              troff requests: .open, .opena, .pso, .sy, and .pi.  For security
              reasons, safer mode is enabled by default.

       -t     Preprocess with tbl.

       -T dev Set output device to dev.  For this device, troff generates  the
              intermediate  output;  see  groff_out(5).   Then  groff  calls a
              postprocessor to convert  troff’s  intermediate  output  to  its
              final format.  Real devices in groff are

                      dvi    TeX DVI format (postprocessor is grodvi).

                      html   xhtml  HTML  and  XHTML output (preprocessors are
                             soelim   and   pre-grohtml,   postprocessor    is

                      lbp    Canon  CAPSL  printers  (LBP-4  and  LBP-8 series
                             laser printers; postprocessor is grolbp).

                      lj4    HP   LaserJet4   compatible   (or   other    PCL5
                             compatible) printers (postprocessor is grolj4).

                      ps     PostScript output (postprocessor is grops).

              For  the  following  TTY output devices (postprocessor is always
              grotty), -T selects the output encoding:

                      ascii  7bit ASCII.

                      cp1047 Latin-1 character set for EBCDIC hosts.

                      latin1 ISO 8859-1.

                      utf8   Unicode character set in UTF-8 encoding.

              The following arguments select gxditview as the  ‘postprocessor’
              (it is rather a viewing program):

                      X75    75dpi resolution, 10pt document base font.

                      X75-12 75dpi resolution, 12pt document base font.

                      X100   100dpi resolution, 10pt document base font.

                             100dpi resolution, 12pt document base font.

              The default device is ps.

       -U     Unsafe  mode.  Reverts to the (old) unsafe behaviour; see option

       -v     --version  Output  version  information  of  groff  and  of  all
              programs  that are run by it; that is, the given command line is
              parsed in the usual way, passing -v to all subprograms.

       -V     Output the pipeline that would be run by  groff  (as  a  wrapper
              program)  on  the  standard  output,  but do not execute it.  If
              given more than once, the  commands  are  both  printed  on  the
              standard error and run.

       -X     Use  gxditview  instead  of  using  the  usual  postprocessor to
              (pre)view a document.  The printing spooler behavior as outlined
              with  options  -l  and  -L  is  carried  over to gxditview(1) by
              determining  an  argument  for  the  -printCommand   option   of
              gxditview(1).   This  sets  the  default  Print  action  and the
              corresponding menu entry to that value.  -X only  produces  good
              results  with -Tps, -TX75, -TX75-12, -TX100, and -TX100-12.  The
              default resolution for previewing -Tps output is 75dpi; this can
              be  changed  by passing the -resolution option to gxditview, for

                     groff -X -P-resolution -P100 -man foo.1

       -z     Suppress output generated by troff.   Only  error  messages  are

       -Z     Do  not  automatically  postprocess groff intermediate output in
              the usual manner.  This will cause the troff output to appear on
              standard  output,  replacing the usual postprocessor output; see

   Transparent Options
       The following options are transparently handed over  to  the  formatter
       program  troff that is called by groff subsequently.  These options are
       described in more detail in troff(1).

       -a     ASCII approximation of output.

       -b     Backtrace on error or warning.

       -c     Disable color output.  Please consult the grotty(1) man page for
              more details.

       -C     Enable compatibility mode.

       -d cs  -d name=s Define string.

       -E     Disable troff error messages.

       -f fam Set default font family.

       -F dir Set path for font DESC files.

       -i     Process standard input after the specified input files.

       -m name
              Include   macro   file   name.tmac   (or;  see  also

       -M dir Path for macro files.

       -n num Number the first page num.

       -o list
              Output only pages in list.

       -r cn  -r name=n Set number register.

       -w name
              Enable warning name.

       -W name
              disable warning name.


       The groff system implements the infrastructure of classical  roff;  see
       roff(7) for a survey on how a roff system works in general.  Due to the
       front-end programs available within the groff system,  using  groff  is
       much easier than classical roff.  This section gives an overview of the
       parts that constitute the groff system.  It  complements  roff(7)  with
       groff-specific  features.   This  section can be regarded as a guide to
       the documentation around the groff system.

   Paper Size
       The virtual paper size used by troff to format the input is  controlled
       globally  with  the  requests .po, .pl, and .ll.  See groff_tmac(5) for
       the ‘papersize’ macro package which provides a convenient interface.

       The physical paper size, giving the  actual  dimensions  of  the  paper
       sheets,  is  controlled  by  output devices like grops with the command
       line options -p and -l.  See groff_font(5) and the  man  pages  of  the
       output devices for more details.  groff uses the command line option -P
       to pass options to output devices; for example, the  following  selects
       A4 paper in landscape orientation for the PS device:

              groff -Tps -P-pa4 -P-l ...

       The  groff program is a wrapper around the troff(1) program.  It allows
       to specify the preprocessors by command line options and  automatically
       runs  the  postprocessor  that  is appropriate for the selected device.
       Doing so, the sometimes tedious piping mechanism of  classical  roff(7)
       can be avoided.

       The  grog(1) program can be used for guessing the correct groff command
       line to format a file.

       The groffer(1) program is an allround-viewer for groff  files  and  man

       The   groff   preprocessors  are  reimplementations  of  the  classical
       preprocessors with moderate  extensions.   The  standard  preprocessors
       distributed with the groff package are

       eqn(1) for mathematical formulæ,

       grn(1) for including gremlin(1) pictures,

       pic(1) for drawing diagrams,

              for chemical structure diagrams,

              for bibliographic references,

              for including macro files from standard locations,


       tbl(1) for tables.

       A new preprocessor not available in classical troff is preconv(1) which
       converts various input encodings to something groff can understand.  It
       is always run first before any other preprocessor.

       Besides   these,   there  are  some  internal  preprocessors  that  are
       automatically run with some devices.  These aren’t visible to the user.

   Macro Packages
       Macro  packages  can  be  included  by  option  -m.   The  groff system
       implements and extends all classical macro packages in a compatible way
       and  adds  some  packages  of  its  own.  Actually, the following macro
       packages come with groff:

       man    The traditional man page format; see groff_man(7).   It  can  be
              specified on the command line as -man or -m man.

       mandoc The  general  package for man pages; it automatically recognizes
              whether the documents uses  the  man  or  the  mdoc  format  and
              branches   to  the  corresponding  macro  package.   It  can  be
              specified on the command line as -mandoc or -m mandoc.

       mdoc   The BSD-style man page format; see  groff_mdoc(7).   It  can  be
              specified on the command line as -mdoc or -m mdoc.

       me     The  classical  me  document format; see groff_me(7).  It can be
              specified on the command line as -me or -m me.

       mm     The classical mm document format; see groff_mm(7).   It  can  be
              specified on the command line as -mm or -m mm.

       ms     The  classical  ms  document format; see groff_ms(7).  It can be
              specified on the command line as -ms or -m ms.

       www    HTML-like macros for inclusion in arbitrary groff documents; see

       Details  on  the naming of macro files and their placement can be found
       in groff_tmac(5); this  man  page  also  documents  some  other,  minor
       auxiliary macro packages not mentioned here.

   Programming Language
       General concepts common to all roff programming languages are described
       in roff(7).

       The groff extensions to the classical troff language are documented  in

       The  groff  language  as a whole is described in the (still incomplete)
       groff info file; a short (but  complete)  reference  can  be  found  in

       The  central  roff  formatter  within the groff system is troff(1).  It
       provides the features of both the classical troff and nroff, as well as
       the  groff  extensions.  The command line option -C switches troff into
       compatibility mode which tries to emulate classical  roff  as  much  as

       There  is  a  shell  script  nroff(1)  that  emulates  the  behavior of
       classical nroff.  It tries to automatically select  the  proper  output
       encoding, according to the current locale.

       The  formatter program generates intermediate output; see groff_out(7).

       In roff, the output targets are called devices.   A  device  can  be  a
       piece  of  hardware,  e.g.,  a  printer,  or a software file format.  A
       device is specified by  the  option  -T.   The  groff  devices  are  as

       ascii  Text output using the ascii(7) character set.

       cp1047 Text  output using the EBCDIC code page IBM cp1047 (e.g., OS/390

       dvi    TeX DVI format.

       html   HTML output.

       latin1 Text output using the ISO Latin-1 (ISO  8859-1)  character  set;
              see iso_8859_1(7).

       lbp    Output  for  Canon  CAPSL printers (LBP-4 and LBP-8 series laser

       lj4    HP LaserJet4-compatible (or other PCL5-compatible) printers.

       ps     PostScript output; suitable for  printers  and  previewers  like

       utf8   Text  output  using  the  Unicode (ISO 10646) character set with
              UTF-8 encoding; see unicode(7).

       xhtml  XHTML output.

       X75    75dpi  X  Window  System  output  suitable  for  the  previewers
              xditview(1x)  and  gxditview(1).   A variant for a 12pt document
              base font is X75-12.

       X100   100dpi X  Window  System  output  suitable  for  the  previewers
              xditview(1x)  and  gxditview(1).   A variant for a 12pt document
              base font is X100-12.

       The postprocessor to be used for a device is specified by  the  postpro
       command in the device description file; see groff_font(5).  This can be
       overridden with the -X option.

       The default device is ps.

       groff provides 3 hardware postprocessors:

              for some Canon printers,

              for printers compatible to the HP LaserJet 4 and PCL5,

              for text output using various encodings, e.g., on  text-oriented
              terminals or line-printers.

       Today,  most  printing  or drawing hardware is handled by the operating
       system, by device drivers, or by software interfaces, usually accepting
       PostScript.  Consequently, there isn’t an urgent need for more hardware
       device postprocessors.

       The groff software devices for  conversion  into  other  document  file
       formats are

              for the DVI format,

              for HTML and XHTML formats,

              for PostScript.

       Combined  with  the  many existing free conversion tools this should be
       sufficient to convert a troff document into virtually any existing data

       The following utility programs around groff are available.

              Add  information  to  troff  font description files for use with

              Create font description files for PostScript device.

              Convert an eqn image into a cropped image.

              Mark differences between groff, nroff, or troff files.

              Convert a grap diagram into a cropped bitmap image.

              General viewer program for groff files and man pages.

              The groff X viewer, the GNU version of xditview.

              Create font description files for lj4 device.

              Make inverted index for bibliographic databases.

              Search bibliographic databases.

              Interactively search bibliographic databases.

              Create PDF documents using groff.

              Translate a PostScript font in .pfb format to ASCII.

              Convert a pic diagram into a cropped image.

              Create font description files for TeX DVI device.

              roff viewer distributed with X window.

              Convert X font metrics into GNU troff font metrics.


       Normally, the path separator in the following environment variables  is
       the  colon;  this  may  vary  depending  on  the operating system.  For
       example, DOS and Windows use a semicolon instead.

              This search path, followed by $PATH, is used for  commands  that
              are  executed  by  groff.   If  it is not set then the directory
              where the groff binaries were installed is prepended to PATH.

              When there is a need to run different  roff  implementations  at
              the same time groff provides the facility to prepend a prefix to
              most of its programs that could provoke name  clashings  at  run
              time  (default  is to have none).  Historically, this prefix was
              the character g, but it can be anything.   For  example,  gtroff
              stood  for groff’s troff, gtbl for the groff version of tbl.  By
              setting GROFF_COMMAND_PREFIX to different values, the  different
              roff installations can be addressed.  More exactly, if it is set
              to prefix xxx then groff as a wrapper program  internally  calls
              xxxtroff   instead   of   troff.    This  also  applies  to  the
              preprocessors eqn, grn, pic, refer,  tbl,  soelim,  and  to  the
              utilities  indxbib  and lookbib.  This feature does not apply to
              any programs different from the ones above (most  notably  groff
              itself) since they are unique to the groff package.

              The  value  of  this  environment value is passed to the preconv
              preprocessor to select the encoding  of  input  files.   Setting
              this  option  implies  groff’s  command line option -k (this is,
              groff actually always calls preconv).  If set without  a  value,
              groff  calls  preconv without arguments.  An explicit -K command
              line  option  overrides  the  value  of   GROFF_ENCODING.    See
              preconv(1) for details.

              A  list  of  directories  in  which  to  search  for the devname
              directory in addition to the default  ones.   See  troff(1)  and
              groff_font(5) for more details.

              A  list  of  directories  in  which to search for macro files in
              addition  to  the  default  directories.    See   troff(1)   and
              groff_tmac(5) for more details.

              The  directory in which temporary files are created.  If this is
              not set but the environment variable TMPDIR  instead,  temporary
              files  are  created  in  the  directory  $TMPDIR.  On MS-DOS and
              Windows 32 platforms, the environment variables TMP and TEMP (in
              that  order)  are  searched also, after GROFF_TMPDIR and TMPDIR.
              Otherwise, temporary files are created in /tmp.   The  refer(1),
              groffer(1),  grohtml(1),  and  grops(1)  commands  use temporary

              Preset the default device.  If this is not set the ps device  is
              used  as default.  This device name is overwritten by the option


       There are some directories in which groff  installs  all  of  its  data
       files.   Due  to  different  installation habits on different operating
       systems, their locations are not absolutely fixed, but  their  function
       is clearly defined and coincides on all systems.

   groff Macro Directory
       This  contains  all  information  related to macro packages.  Note that
       more than a single directory is searched for those files as  documented
       in  groff_tmac(5).   For  the  groff installation corresponding to this
       document, it is located at /usr/share/groff/1.20.1/tmac.  The following
       files contained in the groff macro directory have a special meaning:

              Initialization  file  for  troff.   This is interpreted by troff
              before reading the macro sets and any input.

              Final startup file for troff.  It is parsed after all macro sets
              have been read.

     Macro file for macro package name.

   groff Font Directory
       This  contains  all  information  related to output devices.  Note that
       more than a single directory is searched for those files; see troff(1).
       For  the  groff  installation  corresponding  to  this  document, it is
       located at /usr/share/groff/1.20.1/font.  The following files contained
       in the groff font directory have a special meaning:

              Device description file for device name, see groff_font(5).

              Font file for font F of device name.


       The  following  example illustrates the power of the groff program as a
       wrapper around troff.

       To process a roff file using the preprocessors tbl and pic and  the  me
       macro set, classical troff had to be called by

              pic | tbl | troff -me -Tlatin1 | grotty

       Using groff, this pipe can be shortened to the equivalent command

              groff -p -t -me -T latin1

       An  even  easier  way  to  call  this  is  to  use grog(1) to guess the
       preprocessor and macro options and execute the  generated  command  (by
       using backquotes to specify shell command substitution)

              `grog -Tlatin1`

       The simplest way is to view the contents in an automated way by calling



       On EBCDIC hosts (e.g., OS/390 Unix), output devices  ascii  and  latin1
       aren’t available.  Similarly, output for EBCDIC code page cp1047 is not
       available on ASCII based operating systems.

       Report bugs to the groff maling list Include a complete, self-contained
       example  that allows the bug to be reproduced, and say which version of
       groff you are using.


       Information on how to get groff and related information is available at
       the  groff  GNU  website  The  most recent released version of groff is
       available at the groff development site

       Three groff mailing lists are available:

              for reporting bugs

              for general discussion of groff,

              the  groff  commit  list  a  read-only  list  showing  logs   of
              commitments to the CVS repository.

       Details  on CVS access and much more can be found in the file README at
       the top directory of the groff source package.

       There is a free implementation of the grap preprocessor, written by Ted
       Faber  The  actual version can be found at the grap website This is the
       only grap version supported by groff.


       Copyright © 1989, 2002, 2003, 2004, 2005, 2006, 2007, 2008,  2009  Free
       Software Foundation, Inc.

       This  document  is  distributed  under  the  terms of the FDL (GNU Free
       Documentation License) version 1.3 or later.  You should have  received
       a  copy  of the FDL on your system, it is also available on-line at the
       GNU copyleft site

       This document is based on the original groff man page written by  James
       Clark  It  was  rewritten,  enhanced,  and put under the FDL license by
       Bernd Warken.  It is maintained by Werner Lemberg

       groff is a GNU free software project.  All parts of the  groff  package
       are  protected  by  GNU  copyleft  licenses.   The  software  files are
       distributed under the terms of the GNU General  Public  License  (GPL),
       while  the  documentation  files  mostly use the GNU Free Documentation
       License (FDL).


       The groff info file contains all information on the groff system within
       a  single document, providing many examples and background information.
       See info(1) on how to read it.

       Due to its complex structure, the groff  system  has  many  man  pages.
       They can be read with man(1) or groffer(1).

       Introduction, history and further readings:

       Viewer for groff files:
              groffer(1), gxditview(1), xditview(1x).

       Wrapper programs for formatters:
              groff(1), grog(1).

       Roff preprocessors:
              eqn(1),   grn(1),   pic(1),   chem(1),   preconv(1),   refer(1),
              soelim(1), tbl(1), grap(1).

       Roff language with the groff extensions:
              groff(7), groff_char(7), groff_diff(7), groff_font(5).

       Roff formatter programs:
              nroff(1), troff(1), ditroff(7).

       The intermediate output language:

       Postprocessors for the output devices:
              grodvi(1),  grohtml(1),   grolbp(1),   grolj4(1),   lj4_font(5),
              grops(1), grotty(1).

       Groff macro packages and macro-specific utilities:
              groff_tmac(5),    groff_man(7),    groff_mdoc(7),   groff_me(7),
              groff_mm(7),    groff_mmse(7),    groff_mom(7),     groff_ms(7),
              groff_www(7), groff_trace(7), mmroff(7).

       The following utilities are available:
              addftinfo(1),     afmtodit(1),     eqn2graph(1),     gdiffmk(1),
              grap2graph(1),    groffer(1),     gxditview(1),     hpftodit(1),
              indxbib(1),   lkbib(1),   lookbib(1),   pdfroff(1),  pfbtops(1),
              pic2graph(1), tfmtodit(1), xtotroff(1).