Provided by: groff-base_1.22.4-8build1_amd64 bug


       groff - front-end for the groff document formatting system


       groff [-abcegijklpstzCEGNRSUVXZ] [-d cs] [-D arg] [-f fam] [-F dir] [-I dir] [-K arg]
             [-L arg] [-m name] [-M dir] [-n num] [-o list] [-P arg] [-r cn] [-T dev] [-w name]
             [-W name] [file ...]

       groff -h
       groff --help

       groff -v [option ...]
       groff --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 control of 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.  Whitespace is permitted
       between a command-line option and its argument.  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

       -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.  Implies -p.

       --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 \X'ps: import' ,
              \X'ps: file' and  \X'pdf:  pdfpic'  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 option.

       -j     Preprocess with chem.  Implies -p.

       -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

       -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

       -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).

                     xhtml  HTML  and  XHTML  output  (preprocessors  are soelim and pre-grohtml,
                            postprocessor is post-grohtml).

                     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).

                     pdf    Portable Document Format (PDF) output (postprocessor is gropdf).

              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.  This mode has the most
                            useful fonts for TTY mode, so it is the best mode for TTY output.

              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 -S.

              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

       -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 example

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

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

       -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 groff_out(5).

   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 device DESC files.

       -i     Process standard input after the specified input files.

       -m name
              Include macro file name.tmac (or; see also groff_tmac(5).

       -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.  See troff(1) for names.

       -W name
              disable warning name.  See troff(1) for names.


       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 one 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

       The groffer(1) program is an all-around viewer for groff files and man pages.

       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 formulae,

       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 groff_www(7).

       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

   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 groff_diff(7).

       An overview of language features, including all supported escapes  and  requests,  can  be
       found in groff(7).

       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 possible.

       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 follows.

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

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

       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 printers).

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

       ps     PostScript output; suitable for printers and previewers like gv(1).

       pdf    PDF files; suitable for viewing with tools such as evince(1) and okular(1).

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

       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

       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.

              for PDF.

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

       The following utility programs around groff are available.

              Add information to troff font description files for use with groff.

              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 historically distributed with the X Window System.

              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

              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 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 files.

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


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

       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

              `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


       groff installs files in varying locations depending on its compile-time configuration.  On
       this installation, the following locations are used.

              Application defaults directory for gxditview(1).

              Directory containing groff's executable commands.

              List of common words for indxbib(1).

              Directory for data files.

              Default index for lkbib(1) and refer(1).

              Documentation directory.

              Example directory.

              Font directory.

              HTML documentation directory.

              Legacy font directory.

              Local font directory.

              Local macro package (tmac file) directory.

              Macro package (tmac file) directory.

              Font directory for compatibility with old versions of groff; see grops(1).

              PDF documentation directory.

              System macro package (tmac file) directory.

   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/1.22.4/
       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/1.22.4/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.


       Information  on how to get groff and related information is available at the groff page of
       the GNU website ⟨⟩.

       Three groff mailing lists are available:

              bug tracker activity (read-only) ⟨⟩;

              general discussion ⟨⟩; and

              commit  activity  (read-only)  ⟨⟩,  which  reports  changes  to
              groff's source code repository by its developers.

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

       A free implementation of the grap preprocessor, written by Ted Faber ⟨⟩,
       can  be  found  at the grap website ⟨⟩.
       This is the only grap supported by groff.


       groff was written by James Clark ⟨⟩.  This document was rewritten, enhanced,
       and put under the FDL license in 2002 by Bernd Warken ⟨⟩.


       Groff:  The  GNU  Implementation  of  troff, by Trent A. Fisher and Werner Lemberg, is the
       primary groff manual.  You can browse it interactively with “info groff”.

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

       But  there are special sections of man pages.  groff has man pages in sections 1, 5,and 7.
       When there are several man pages with the same name in the same man section, the one  with
       the  lowest section is should as first.  The other man pages can be shown anyway by adding
       the section number as argument before the man page name.  Reading the man page  about  the
       groff language is done by one of
              man 7 groff
              groffer 7 groff

       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), gropdf(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)
              (only in Swedish locales), groff_mom(7), groff_ms(7), groff_www(7), groff_trace(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).