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
       files that include formatting commands to produce output in PostScript,
       PDF, HTML, DVI, 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 the typesetter from AT&T Unix,
       groff is present on most POSIX systems owing to its long association
       with Unix manuals (including man pages).  It and its predecessor are
       notable for their production of several best-selling software
       engineering texts.  groff is capable of producing typographically
       sophisticated documents while consuming minimal system resources.

       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 Set fallback input encoding used by preconv(1) to enc; 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.
              It is passed to soelim(1) and the output driver, and grn is
              passed an -M option with dir as its argument.

       -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 program.  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
              program.

       -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 refer because most refer options have equivalent
              language elements that can be specified within the document.

       -s     Run soelim(1) preprocessor.

       -S     Operate in “safer” mode; see -U below for its opposite.  For
              security reasons, safer mode is enabled by default.

       -t     Run tbl(1) preprocessor.

       -T dev Direct troff to format the input for the output device dev.
              groff then calls an output driver to convert troff's output to a
              form appropriate for dev; see subsection “Output devices” below.

       -U     Operate in unsafe mode: pass the -U option to pic and troff.

       -v
       --version
              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, but do not execute it.  If given more than once, groff
              both writes and runs the pipeline.

       -X     Use gxditview(1) instead of the usual postprocessor to (pre)view
              a document on an X11 display.  Combining this option with -Tps
              uses the font metrics of the PostScript device, whereas the
              -TX75 and -TX100 options use the metrics of X11 fonts.

       -Z     Disable postprocessing.  troff output will appear 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 cs
       -d name=string
              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 name
              Process name.tmac before input files.

       -M dir Search directory dir for macro files.

       -n num Number the first page num.

       -o list
              Output only pages in list.

       -r cnumeric-expression
       -r register=numeric-expression
              Define register.

       -w name
       -W name
              Enable (-w) or inhibit (-W) emission of warnings in category
              name.

       -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”), a suite of utilities,
       and the formatter troff 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 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.html

   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
       In GNU roff, the page dimensions for the formatter troff and for output
       devices are handled separately.  In the formatter, requests are used to
       set the page length (.pl), page offset (or left margin, .po), and line
       length (.ll).  The right margin is not explicitly configured; the
       combination of page offset and line length provides the information
       necessary to derive it.  The papersize macro package, automatically
       loaded by troff, provides an interface for configuring page dimensions
       by convenient names, like “letter” or “A4”; see groff_tmac(5).  The
       formatter's default in this installation is “letter”.

       It is up to each macro package to respect the page dimensions
       configured in this way.  Some offer alternative mechanisms.

       For each output device, the size of the output medium can be set in its
       DESC file.  Most output drivers also recognize a command-line option -p
       to override the default dimensions and an option -l to use landscape
       orientation.  See groff_font(5) for a description of the papersize
       directive, which takes an argument of the same form as -p.  The output
       driver's man page, such as grops(1), may also be helpful.  groff uses
       the command-line option -P to pass options to output devices; for
       example, use the following for PostScript output on A4 paper in
       landscape orientation.

              groff -Tps -dpaper=a4l -P-pa4 -P-l -ms foo.ms > foo.ps

   Front end
       The groff program is a wrapper around the troff(1) program.  It allows
       one to specify preprocessors via command-line options and automatically
       runs the appropriate postprocessor for the selected output device.
       Doing so, the manual construction of pipelines or management of
       temporary files required of users of traditional roff(7) systems can be
       avoided.  Use the grog(1) program 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(7).  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 a roff input file (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 formulæ 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.

       Macro packages can be loaded prior to any roff input documents with the
       -m option.  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/homebrew/Cellar/groff/1.23.0_1/share/doc/groff-1.23.0/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 program
       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.

       cp1047   for terminals using the IBM code page 1047 character set and
                encoding.

       dvi      for TeX DVI format.

       html
       xhtml    for HTML and XHTML output, respectively.

       latin1   for terminals using the ISO Latin-1 (ISO 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, cp1047, 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 with a failure status if there was a problem parsing its
       arguments and a successful status if either of the options -h or --help
       was specified.  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 0 if a command exited with a failure status,
       bit 1 if a command was terminated with a signal, and bit 2 if a command
       could not be executed.  (Thus, if all three misfortunes befell one's
       pipeline, groff would exit with status 2^0 + 2^1 + 2^2 = 1+2+4 = 7.)
       To troubleshoot pipeline problems, you may wish to 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
       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
              This search path, followed by PATH, is used to locate commands
              executed by groff.  If it is not set, the installation directory
              of the GNU roff executables,
              /opt/homebrew/Cellar/groff/1.23.0_1/bin, is searched before
              PATH.

       GROFF_COMMAND_PREFIX
              GNU roff can be configured at compile time to apply a prefix to
              the names of the programs it provides that had a counterpart 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 nroff; the preprocessors
              eqn, grn, pic, refer, tbl, and soelim; and the utilities indxbib
              and lookbib.

       GROFF_ENCODING
              The value of this variable is passed to the preconv(1)
              preprocessor's -e option to select the character encoding of
              input files.  This variable's existence implies the groff option
              -k.  If set but empty, groff calls 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 files in this list of directories.  See troff(1) and
              groff_tmac(5).

       GROFF_TMPDIR
              Create temporary files in this directory.  If not set, but the
              environment variable TMPDIR is set, temporary files are created
              there 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
              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 localtime(3)
              when the formatter starts up and stored in registers usable by
              documents and macro packages.

       TZ     The time zone to use when converting the current time (or value
              of SOURCE_DATE_EPOCH) to human-readable form; see tzset(3).

Examples
       roff systems are best known for formatting man pages.  Once a man(1)
       librarian program has located a man page, it may execute a groff
       command much like the following.
              groff -t -man -Tutf8 /usr/share/man/man1/groff.1
       The librarian will also pipe the output through a pager, which might
       not interpret the SGR terminal escape sequences groff emits for
       boldface, underlining, or italics; 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

       Using groff, this pipe can be shortened to an equivalent command.

              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, cp1047, 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).

       On EBCDIC hosts such as OS/390 Unix, the output devices ascii and
       latin1 aren't available.  Conversely, the output device cp1047 is not
       available on systems based on the ISO 646 or ISO 8859 character
       encoding standards.

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

       /opt/homebrew/Cellar/groff/1.23.0_1/bin
              Directory containing groff's executable commands.

       /opt/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0/eign
              List of common words for indxbib(1).

       /opt/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0
              Directory for data files.

       /usr/dict/papers/Ind
              Default index for lkbib(1) and refer(1).

       /opt/homebrew/Cellar/groff/1.23.0_1/share/doc/groff-1.23.0
              Documentation directory.

       /opt/homebrew/Cellar/groff/1.23.0_1/share/doc/groff-1.23.0/examples
              Example directory.

       /opt/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0/font
              Font directory.

       /opt/homebrew/Cellar/groff/1.23.0_1/share/doc/groff-1.23.0/html
              HTML documentation directory.

       /usr/lib/font
              Legacy font directory.

       /opt/homebrew/etc/groff/site-font
              Local font directory.

       /opt/homebrew/etc/groff/site-tmac
              Local macro package (tmac file) directory.

       /opt/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0/tmac
              Macro package (tmac file) directory.

       /opt/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0/oldfont
              Font directory for compatibility with old versions of groff; see
              grops(1).

       /opt/homebrew/Cellar/groff/1.23.0_1/share/doc/groff-1.23.0/pdf
              PDF documentation directory.

   groff macro directory
       Most macro files supplied with GNU roff are stored in
       /opt/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0/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/homebrew/Cellar/groff/1.23.0_1/share/groff/1.23.0/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”.

       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 and package-specific utilities:
              groff_hdtbl(7), groff_man(7), groff_man_style(7), groff_mdoc(7),
              groff_me(7), groff_mm(7), groff_mmse(7), mmroff(1),
              groff_mom(7), pdfmom(1), 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(7), groff_char(7), groff_diff(7), groff_font(5),
              groff_tmac(5)

       Intermediate output language:
              groff_out(5)

       Formatter program:
              troff(1)

       Formatter wrappers:
              nroff(1), pdfroff(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 1.23.0                      5 July 2023                         groff(1)