groff(1) General Commands Manual groff(1)
Name
groff - front end to the GNU roff document formatting system
Synopsis
groff [-abcCeEgGijklNpRsStUVXzZ] [-d ctext] [-d string=text]
[-D fallback-encoding] [-f font-family] [-F font-directory]
[-I inclusion-directory] [-K input-encoding]
[-L spooler-argument] [-m macro-package] [-M macro-directory]
[-n page-number] [-o page-list] [-P postprocessor-argument]
[-r cnumeric-expression] [-r register=numeric-expression]
[-T output-device] [-w warning-category] [-W warning-category]
[file ...]
groff -h
groff --help
groff -v [option ...] [file ...]
groff --version [option ...] [file ...]
Description
groff is the primary front end to the GNU roff document formatting
system. GNU roff is a typesetting system that reads plain text input
that includes formatting commands to produce output in PostScript, PDF,
HTML, or other formats, or for display to a terminal. Formatting
commands can be low-level typesetting primitives, macros from a
supplied package, or user-defined macros. All three approaches can be
combined. If no file operands are specified, or if file is "-", groff
reads the standard input stream.
A reimplementation and extension of troff and other programs from AT&T
Unix, groff is widely available on POSIX and other systems owing to its
long association with Unix manuals, including man pages. It and its
predecessor have produced several best-selling software engineering
texts. groff can create typographically sophisticated documents while
consuming minimal system resources.
Like its predecessor "troff", the term "groff" affords two popular
pronunciations: as one syllable (like the surname), rhyming with
"trough", or as "jee-roff", in analogy to the Bell Labs pronunciation
"tee-roff". Little risk of confusion exists; use whichever suits you.
The groff command orchestrates the execution of preprocessors, the
transformation of input documents into a device-independent page
description language, and the production of output from that language.
Options
-h and --help display a usage message and exit.
Because groff is intended to subsume most users' direct invocations of
the troff(1) formatter, the two programs share a set of options.
However, groff has some options that troff does not share, and others
which groff interprets differently. At the same time, not all valid
troff options can be given to groff.
groff-specific options
The following options either do not exist in GNU troff or are
interpreted differently by groff.
-D enc Use enc as preconv(1)'s fallback input encoding; implies -k.
-e Run eqn(1) preprocessor.
-g Run grn(1) preprocessor.
-G Run grap(1) preprocessor; implies -p.
-I dir Works as troff's option (see below), but also implies -g and
-s. groff passes -I options and their arguments to soelim(1),
troff(1), and output drivers; with the option letter changed
to -M, it passes the same arguments to grn(1).
-j Run chem(1) preprocessor; implies -p.
-k Run preconv(1) preprocessor. Refer to its man page for its
behavior if neither of groff's -K or -D options is also
specified.
-K enc Set input encoding used by preconv(1) to enc; implies -k.
-l Send the output to a spooler program for printing. The
"print" directive in the device description file specifies the
default command to be used; see groff_font(5). If no such
directive is present for the output device, output is piped to
lpr(1). See options -L and -X.
-L arg Pass arg to the print spooler. If multiple args are required,
pass each with a separate -L option. groff does not prefix an
option dash to arg before passing it to the spooler.
-M Works as troff's option (see below), but is also passed to
eqn(1), grap(1), and grn(1).
-N Prohibit newlines between eqn delimiters: pass -N to eqn(1).
-p Run pic(1) preprocessor.
-P arg Pass arg to the postprocessor. If multiple args are required,
pass each with a separate -P option. groff does not prefix an
option dash to arg before passing it to the postprocessor.
-R Run refer(1) preprocessor. No mechanism is provided for
passing arguments to it; most refer options have equivalent
language elements that can be specified within the document.
-s Run soelim(1) preprocessor.
-S Enable safer mode and ignore any subsequent -U option. groff
passes the -S option to pic(1) and troff(1).
-t Run tbl(1) preprocessor.
-T dev Prepare output for device dev. groff passes the -T option and
its argument to troff, then (unless the -Z option is used)
runs an output driver to convert troff's output to a form
appropriate for dev; see subsection "Output devices" below.
-U Operate in unsafe mode. groff passes the -U option to pic(1)
and troff(1).
--version
-v Write version information for groff and all programs run by it
to the standard output stream; that is, the given command line
is processed in the usual way, passing -v to the formatter and
any pre- or postprocessors invoked.
-V Output the pipeline that groff would run to the standard
output stream and exit. If given more than once, groff both
writes the pipeline to the standard error stream and runs it.
-X Use gxditview(1) instead of the usual postprocessor to
(pre)view a document on an X11 display. Combining this option
with "-T ps" uses the font metrics of the PostScript device,
whereas the "-T X75", "-T X75-12" "-T X100", and "-T X100-12"
options use the metrics of X11 fonts.
-Z Disable postprocessing. troff output appears on the standard
output stream (unless suppressed with -z); see groff_out(5)
for a description of this format.
Transparent options
The following options are passed as-is to the formatter program
troff(1) and described in more detail in its man page.
-a Generate a plain text approximation of the typeset output.
-b Write a backtrace to the standard error stream on each error
or warning.
-c Start with color output disabled.
-C Enable AT&T troff compatibility mode; implies -c.
-d ctext
-d string=text
Define string.
-E Inhibit troff error messages; implies -Ww.
-f fam Set default font family.
-F dir Search in directory dir for the selected output device's
directory of device and font description files.
-i Process standard input after the specified input files.
-I dir Search dir for input files.
-m mac Read macro package mac before input. groff passes -m options
and their arguments to eqn(1), grap(1), and grn(1).
-M dir Search directory dir for macro files. groff passes -M options
and their arguments to eqn(1), grap(1), and grn(1).
-n num Begin numbering pages at num.
-o list Output only pages in list.
-r cnumeric-expression
-r register=numeric-expression
Define register.
-S Enable safer mode and ignore any subsequent -U option.
-U Operate in unsafe mode.
-w cat
-W cat Enable and inhibit, respectively, warnings in category cat.
-z Suppress formatted device-independent output of troff.
Usage
The architecture of the GNU roff system follows that of other device-
independent roff implementations, comprising preprocessors, macro
packages, output drivers (or "postprocessors"), and a suite of
utilities, with the formatter program troff(1) at its heart. See
roff(7) for a survey of how a roff system works.
The front end programs available in the GNU roff system make it easier
to use than traditional roffs that required the construction of
pipelines or use of temporary files to carry a source document from
maintainable form to device-ready output. The discussion below
summarizes the constituent parts of the GNU roff system. It
complements roff(7) with groff-specific information.
Getting started
Those who prefer to learn by experimenting or are desirous of rapid
feedback from the system may wish to start with a "Hello, world!"
document.
$ echo "Hello, world!" | groff -Tascii | sed '/^$/d'
Hello, world!
We used a sed(1) command only to eliminate the 65 blank lines that
would otherwise flood the terminal screen. (roff systems were
developed in the days of paper-based terminals with 66 lines to a
page.)
Today's users may prefer output to a UTF-8-capable terminal.
$ echo "Hello, world!" | groff -Tutf8 | sed '/^$/d'
Producing PDF, HTML, or TeX's DVI is also straightforward. The hard
part may be selecting a viewer program for the output.
$ echo "Hello, world!" | groff -Tpdf > hello.pdf
$ evince hello.pdf
$ echo "Hello, world!" | groff -Thtml > hello.html
$ firefox hello.html
$ echo "Hello, world!" | groff -Tdvi > hello.dvi
$ xdvi hello.dvi
Using groff as a REPL
Those with a programmer's bent may be pleased to know that they can use
groff in a read-evaluate-print loop (REPL). Doing so can be handy to
verify one's understanding of the formatter's behavior and/or the
syntax it accepts. Turning on all warnings with -ww can aid this goal.
$ groff -ww -Tutf8
\# This is a comment. Let's define a register.
.nr a 1
\# Do integer arithmetic with operators evaluated left-to-right.
.nr b \n[a]+5/2
\# Let's get the result on the standard error stream.
.tm \n[b]
3
\# Now we'll define a string.
.ds name Leslie\" This is another form of comment.
.nr b (\n[a] + (7/2))
\# Center the next two text input lines.
.ce 2
Hi, \*[name].
Your secret number is \n[b].
\# We will see that the division rounded toward zero.
It is
\# Here's an if-else control structure.
.ie (\n[b] % 2) odd.
.el even.
\# This trick sets the page length to the current vertical
\# position, so that blank lines don't spew when we're done.
.pl \n[nl]u
<Control-D>
Hi, Leslie.
Your secret number is 4.
It is even.
Paper format
The formatter reads the device description file DESC for the selected
output device when it starts; page dimensions declared there are used
if present. groff's build process configures a default page format and
writes it to typesetters' DESC files. This installation defaults to
"letter". If the DESC file lacks this information, the formatter and
output driver use a page length of "11i" (eleven inches) for
compatibility with AT&T troff. See groff_font(5).
In the formatter, the pl request changes the page length, but macro
packages often do not support alteration of the paper format within a
document. One might, for instance, want to switch between portrait and
landscape orientations. Macro packages lack a consistent approach to
configuration of parameters dependent on the paper format; some, like
ms, benefit from a preamble in the document prior to the first macro
call, while others, like mm, instead require the specification of
registers on the command line, or otherwise before its macro file is
interpreted, to configure page dimensions.
Output drivers for typesetters also recognize command-line options -p
to override the default page dimensions and -l to use landscape
orientation. The output driver's man page, such as grops(1), may be
helpful.
groff's "-d paper" command-line option is a convenient means of setting
the paper format; see groff_tmac(5). Combine it with appropriate -P
options for the output driver, overriding its defaults. The following
command formats for PostScript on A4 paper in landscape orientation.
$ groff -T ps -d paper=a4l -P -pa4 -P -l -ms my.ms >my.ps
Front end
The groff program wraps troff(1), allowing one to specify preprocessors
via command-line options and running the appropriate output driver for
the selected output device. This convenience avoids the manual
construction of pipelines or management of temporary files required of
users of traditional roff(7) systems. Use grog(1) to infer an
appropriate groff command line to format a document.
Language
Input to a roff system is in plain text interleaved with control lines
and escape sequences. The combination constitutes a document in one of
a family of languages we also call roff; see roff(7) for background.
An overview of GNU roff language syntax and features, including lists
of all supported escape sequences, requests, and predefined registers,
can be found in groff(1). GNU roff extensions to the AT&T troff
language, a common subset of roff dialects extant today, are detailed
in groff_diff(7).
Preprocessors
A preprocessor interprets a domain-specific language that produces roff
language output. Frequently, such input is confined to sections or
regions of roff input (bracketed with macro calls specific to each
preprocessor), which it replaces. Preprocessors therefore often
interpret a subset of roff syntax along with their own language. GNU
roff provides reimplementations of most preprocessors familiar to users
of AT&T troff; these routinely have extended features and/or require
GNU troff to format their output.
tbl lays out tables;
eqn typesets mathematics;
pic draws diagrams;
refer processes bibliographic references;
soelim preprocesses "sourced" input files;
grn renders diagrams;
chem draws chemical structural formulae using pic ;
gperl populates groff registers and strings using
glilypond embeds LilyPond sheet music; and
gpinyin eases Mandarin Chinese input using Hanyu Pinyin.
perl(1)in(1)
A preprocessor unique to GNU roff is preconv(1), which converts various
input encodings to something GNU troff can understand. When used, it
is run before any other preprocessors.
Most preprocessors enclose content between a pair of characteristic
tokens. Such a token must occur at the beginning of an input line and
use the dot control character. Spaces and tabs must not follow the
control character or precede the end of the input line. Deviating from
these rules defeats a token's recognition by the preprocessor. Tokens
are generally preserved in preprocessor output and interpreted as macro
calls subsequently by troff. The ideal preprocessor is not yet
available in groff.
+-------------+-----------------+----------------+
|preprocessor | starting token | ending token |
+=============+=================+================+
| chem | .cstart | .cend |
| eqn | .EQ | .EN |
| grap | .G1 | .G2 |
| grn | .GS | .GE |
| ideal | .IS | .IE |
| | | .IF |
| pic | .PS | .PE |
| | | .PF |
| | | .PY |
| refer | .R1 | .R2 |
| tbl | .TS | .TE |
+-------------+-----------------+----------------+
| glilypond | .lilypond start | .lilypond stop |
| gperl | .Perl start | .Perl stop |
| gpinyin | .pinyin start | .pinyin stop |
+-------------+-----------------+----------------+
Macro packages
Macro files are roff input files designed to produce no output
themselves but instead ease the preparation of other roff documents.
When a macro file is installed at a standard location and suitable for
use by a general audience, it is termed a macro package.
The -m option loads a macro package prior to any roff input documents,
and after performing any string and register assignments directed by -d
and -r options. The GNU roff system implements most well-known macro
packages for AT&T troff in a compatible way and extends them. These
have one- or two-letter names arising from intense practices of naming
economy in early Unix culture, a laconic approach that led to many of
the packages being identified in general usage with the nroff and troff
option letter used to invoke them, sometimes to punning effect, as with
"man" (short for "manual"), and even with the option dash, as in the
case of the s package, much better known as ms or even -ms.
Macro packages serve a variety of purposes. Some are "full-service"
packages, adopting responsibility for page layout among other
fundamental tasks, and defining their own lexicon of macros for
document composition; each such package stands alone and a given
document can use at most one.
an is used to compose man pages in the format originating in
Version 7 Unix (1979); see groff_man(7). It can be specified on
the command line as -man.
doc is used to compose man pages in the format originating in
4.3BSD-Reno (1990); see groff_mdoc(7). It can be specified on
the command line as -mdoc.
e is the Berkeley general-purpose macro suite, developed as an
alternative to AT&T's s; see groff_me(7). It can be specified
on the command line as -me.
m implements the format used by the second-generation AT&T macro
suite for general documents, a successor to s; see groff_mm(7).
It can be specified on the command line as -mm.
om (invariably called "mom") is a modern package written by Peter
Schaffter specifically for GNU roff. Consult the mom HTML
manual <file:///opt/local/share/doc/groff-1.24.1/html/mom/toc
.html> for extensive documentation. She--for mom takes the
female pronoun--can be specified on the command line as -mom.
s is the original AT&T general-purpose document format; see
groff_ms(7). It can be specified on the command line as -ms.
Others are supplemental. For instance, andoc is a wrapper package
specific to GNU roff that recognizes whether a document uses man or
mdoc format and loads the corresponding macro package. It can be
specified on the command line as -mandoc. A man(1) librarian may use
this macro file to delegate loading of the correct macro package; it is
thus unnecessary for man itself to scan the contents of a document to
decide the issue.
Many macro files augment the function of the full-service packages, or
of roff documents that do not employ such a package--the latter are
sometimes characterized as "raw". These auxiliary packages are
described, along with details of macro file naming and placement, in
groff_tmac(5).
Formatters
The formatter, the program that interprets roff language input, is
troff(1). It provides the features of the AT&T troff and nroff
programs as well as many extensions. The command-line option -C
switches troff into compatibility mode, which tries to emulate AT&T
troff as closely as is practical to enable the formatting of documents
written for the older system.
A shell script, nroff(1), emulates the behavior of AT&T nroff. It
attempts to correctly encode the output based on the locale, relieving
the user of the need to specify an output device with the -T option and
is therefore convenient for use with terminal output devices, described
in the next subsection.
GNU troff generates output in a device-independent, but not device-
agnostic, page description language detailed in groff_out(5).
Output devices
troff output is formatted for a particular output device, typically
specified by the -T option to the formatter or a front end. If neither
this option nor the GROFF_TYPESETTER environment variable is used, the
default output device is ps. An output device may be any of the
following.
ascii for terminals using the ISO 646 1991:IRV character set and
encoding, also known as US-ASCII.
dvi for TeX DVI format.
html
xhtml for HTML and XHTML output, respectively.
latin1 for terminals using the ISO Latin-1 (8859-1) character set
and encoding.
lbp for Canon CaPSL printers (LBP-4 and LBP-8 series laser
printers).
lj4 for HP LaserJet4-compatible (or other PCL5-compatible)
printers.
pdf for PDF output.
ps for PostScript output.
utf8 for terminals using the ISO 10646 ("Unicode") character set
in UTF-8 encoding.
X75 for previewing with gxditview using 75 dpi resolution and a
10-point base type size.
X75-12 for previewing with gxditview using 75 dpi resolution and a
12-point base type size.
X100 for previewing with gxditview using 100 dpi resolution and a
10-point base type size.
X100-12 for previewing with gxditview using 100 dpi resolution and a
12-point base type size.
Postprocessors
Any program that interprets the output of GNU troff is a postprocessor.
The postprocessors provided by GNU roff are output drivers, which
prepare a document for viewing or printing. Postprocessors for other
purposes, such as page resequencing or statistical measurement of a
document, are conceivable.
An output driver supports one or more output devices, each with its own
device description file. A device determines its postprocessor with
the postpro directive in its device description file; see
groff_font(5). The -X option overrides this selection, causing
gxditview to serve as the output driver.
grodvi(1)
provides dvi.
grohtml(1)
provides html and xhtml.
grolbp(1)
provides lbp.
grolj4(1)
provides lj4.
gropdf(1)
provides pdf.
grops(1)
provides ps.
grotty(1)
provides ascii, latin1, and utf8.
gxditview(1)
provides X75, X75-12, X100, and X100-12, and additionally can
preview ps.
Utilities
GNU roff includes a suite of utilities.
gdiffmk(1)
marks differences between a pair of roff input files.
grog(1)
infers the groff command a document requires.
Several utilities prepare descriptions of fonts, enabling the formatter
to use them when producing output for a given device.
addftinfo(1)
adds information to AT&T troff font description files to enable
their use with GNU troff.
afmtodit(1)
creates font description files for PostScript Type 1 fonts.
pfbtops(1)
translates a PostScript Type 1 font in PFB (Printer Font Binary)
format to PFA (Printer Font ASCII), which can then be
interpreted by afmtodit.
hpftodit(1)
creates font description files for the HP LaserJet 4 family of
printers.
tfmtodit(1)
creates font description files for the TeX DVI device.
xtotroff(1)
creates font description files for X Window System core fonts.
A trio of tools transform material constructed using roff preprocessor
languages into graphical image files.
eqn2graph(1)
converts an eqn equation into a cropped image.
grap2graph(1)
converts a grap diagram into a cropped image.
pic2graph(1)
converts a pic diagram into a cropped image.
Another set of programs works with the bibliographic data files used by
the refer(1) preprocessor.
indxbib(1)
makes inverted indices for bibliographic databases, speeding
lookup operations on them.
lkbib(1)
searches the databases.
lookbib(1)
interactively searches the databases.
Exit status
groff exits successfully (with status 0) if either of the options -h or
--help is specified, status 2 if the program cannot interpret its
command-line arguments, and status 1 if it encounters an error during
operation. Otherwise, groff runs a pipeline to process its input; if
all commands within the pipeline exit successfully, groff does
likewise. If not, groff's exit status encodes a summary of problems
encountered, setting bit 2 if a command exited with a failure status,
bit 3 if a command was terminated with a signal, and bit 4 if a command
could not be executed. (Thus, if all three misfortunes befall one's
pipeline, groff exits with status 2^2 + 2^3 + 2^4 = 4+8+16 = 28.) To
troubleshoot pipeline problems, re-run the groff command with the -V
option and break the reported pipeline down into separate stages,
inspecting the exit status of, and diagnostic messages emitted by, each
command.
Environment
Environment variables in the host system affect the behavior of
programs supplied by groff as follows. Normally, the path separator in
environment variables ending with PATH is the colon; this may vary
depending on the operating system. For example, Windows uses a
semicolon instead.
GROFF_BIN_PATH
Locate groff commands in these directories, followed by those in
PATH. If not set, the installation directory of GNU roff
executables, /opt/local/bin, is searched before PATH.
GROFF_COMMAND_PREFIX
Apply a prefix to certain GNU roff commands. groff can be
configured at compile time to apply a prefix to the names of
programs it provides that had counterparts in AT&T troff, so
that name collisions are avoided at run time. The default
prefix is empty.
When used, this prefix is conventionally the letter "g". For
example, GNU troff would be installed as gtroff. Besides troff,
the prefix applies to the formatter wrapper nroff; the
preprocessors eqn, grn, pic, refer, tbl, and soelim; and the
utilities indxbib and lookbib.
GROFF_ENCODING
Specify the assumed character encoding of the input. groff
passes its value as an argument to preconv(1) preprocessor's -e
option. This variable's existence implies the groff option -k.
If set but empty, groff runs preconv without an -e option.
groff's -K option overrides GROFF_ENCODING.
GROFF_FONT_PATH
Seek the selected output device's directory of device and font
description files in this list of directories. See troff(1) and
groff_font(5).
GROFF_TMAC_PATH
Seek macro packages in this list of directories. See troff(1)
and groff_tmac(5).
GROFF_TMPDIR
Create temporary files in this directory. If not set, but
TMPDIR is, the latter is used instead. On Windows systems, if
neither of the foregoing are set, the environment variables TMP
and TEMP (in that order) are checked also. Otherwise, temporary
files are created in /tmp. The refer(1), grohtml(1), and
grops(1) commands use temporary files.
GROFF_TYPESETTER
Set the default output device. If empty or not set, ps is used.
The -T option overrides GROFF_TYPESETTER.
SOURCE_DATE_EPOCH
Declare a time stamp (expressed as seconds since the Unix epoch)
to use as the output creation time stamp in place of the current
time. The time is converted to human-readable form using
gmtime(3) and asctime(3) when the formatter starts up and stored
in registers usable by documents and macro packages.
TZ Declare the time zone to use when converting the current time to
human-readable form; see tzset(3). If SOURCE_DATE_EPOCH is
used, it is always converted to human-readable form using UTC.
Examples
roff systems are best known for formatting man pages. A man(1)
librarian program, having located a page, might render it with a groff
command.
groff -t -man -Tutf8 /usr/share/man/man1/groff.1
The librarian will also pipe the output through a pager, which might
not interpret terminal escape sequences groff emits for boldface,
underlining, italics, or hyperlinking; see section "Limitations" below.
To process a roff input file using the preprocessors tbl and pic and
the me macro package in the way to which AT&T troff users were
accustomed, one would type (or script) a pipeline.
pic foo.me | tbl | troff -me -Tutf8 | grotty
Shorten this pipeline to an equivalent command using groff.
groff -p -t -me -T utf8 foo.me
An even easier way to do this is to use grog(1) to guess the
preprocessor and macro options and execute the result by using the
command substitution feature of the shell.
$(grog -Tutf8 foo.me)
Each command-line option to a postprocessor must be specified with any
required leading dashes "-" because groff passes the arguments as-is to
the postprocessor; this permits arbitrary arguments to be transmitted.
For example, to pass a title to the gxditview postprocessor, the shell
commands
groff -X -P -title -P 'trial run' mydoc.t
and
groff -X -Z mydoc.t | gxditview -title 'trial run' -
are equivalent.
Limitations
When paging output for the ascii, latin1, and utf8 devices, programs
like more(1) and less(1) may require command-line options to correctly
handle some terminal escape sequences; see grotty(1).
Installation directories
GNU roff installs files in varying locations depending on its compile-
time configuration. On this installation, the following locations are
used.
/opt/local/bin
Directory containing groff's executable commands.
/opt/local/share/groff/1.24.1/eign
List of common words for indxbib(1).
/opt/local/share/groff/1.24.1
Directory for data files.
/usr/dict/papers/Ind
Default index for lkbib(1) and refer(1).
/opt/local/share/doc/groff-1.24.1
Documentation directory.
/opt/local/share/doc/groff-1.24.1/examples
Example directory.
/opt/local/share/groff/1.24.1/font
Font directory.
/opt/local/share/doc/groff-1.24.1/html
HTML documentation directory.
/usr/lib/font
Legacy font directory.
/opt/local/share/groff/site-font
Local font directory.
/opt/local/share/groff/site-tmac
Local macro package (tmac file) directory.
/opt/local/share/groff/1.24.1/tmac
Macro package (tmac file) directory.
/opt/local/share/groff/1.24.1/oldfont
Font directory for compatibility with old versions of groff; see
grops(1).
/opt/local/share/doc/groff-1.24.1/pdf
PDF documentation directory.
groff macro directory
Most macro files supplied with GNU roff are stored in /opt/local/share/
groff/1.24.1/tmac for the installation corresponding to this document.
As a rule, multiple directories are searched for macro files; see
troff(1). For a catalog of macro files GNU roff provides, see
groff_tmac(5).
groff device and font description directory
Device and font description files supplied with GNU roff are stored in
/opt/local/share/groff/1.24.1/font for the installation corresponding
to this document. As a rule, multiple directories are searched for
device and font description files; see troff(1). For the formats of
these files, see groff_font(5).
Availability
Obtain links to groff releases for download, its source repository,
discussion mailing lists, a support ticket tracker, and further
information from the groff page of the GNU website <http://www.gnu.org/
software/groff>.
A free implementation of the grap preprocessor, written by Ted Faber
<faber@lunabase.org>, can be found at the grap website <http://www
.lunabase.org/~faber/Vault/software/grap/>. groff supports only this
grap.
Authors
groff (both the front-end command and the overall system) was primarily
written by James Clark <jjc@jclark.com>. Contributors to this document
include Clark, Trent A. Fisher, Werner Lemberg <wl@gnu.org>, Bernd
Warken <groff-bernd.warken-72@web.de>, and G. Branden Robinson
<g.branden.robinson@gmail.com>.
See also
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".
A list of all groff man pages follows. A few (grohtml, gropdf,
gxditview, and xtotroff) will be unavailable if their corresponding
programs were disabled during compilation.
Introduction, history, and further reading:
roff(7)
Viewer for groff (and AT&T device-independent troff) documents:
gxditview(1)
Preprocessors:
chem(1), eqn(1), neqn(1), glilypond(1), grn(1), preconv(1),
gperl(1), pic(1), gpinyin(1), refer(1), soelim(1), tbl(1)
Macro packages:
groff_hdtbl(7), groff_man(7), groff_man_style(7), groff_mdoc(7),
groff_me(7), groff_mm(7), groff_mmse(7), groff_mom(7),
groff_ms(7), groff_rfc1345(7), groff_trace(7), groff_www(7)
Bibliographic database management tools:
indxbib(1), lkbib(1), lookbib(1)
Language, conventions, and GNU extensions:
groff(1), groff_char(7), groff_diff(7), groff_font(5),
groff_tmac(5)
Device-independent page description language:
groff_out(5)
Formatter program:
troff(1)
Formatter wrappers:
nroff(1), mmroff(1), pdfmom(1)
Postprocessors for output devices:
grodvi(1), grohtml(1), grolbp(1), grolj4(1), gropdf(1),
grops(1), grotty(1)
Font support utilities:
addftinfo(1), afmtodit(1), hpftodit(1), pfbtops(1), tfmtodit(1),
xtotroff(1)
Graphics conversion utilities:
eqn2graph(1), grap2graph(1), pic2graph(1)
Difference-marking utility:
gdiffmk(1)
"groff guess" utility:
grog(1)
groff 1.24.1 2026-05-15 groff(1)
groff 1.24.1 - Generated Mon May 18 09:28:56 CDT 2026