groffer(1) — Linux manual page

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groffer(1)               General Commands Manual              groffer(1)

Name         top

       groffer - display groff files and man pages on X and tty

Synopsis         top

       groffer [mode-option ...] [groff-option ...] [man-option ...] [X-
               option ...] [--] [filespec ...]

       groffer -h
       groffer --help

       groffer -v
       groffer --version

Description         top

       The groffer program is the easiest way to use groff(1).  It can
       display arbitrary documents written in the groff language, see
       groff(7), or other roff languages, see roff(7), that are
       compatible to the original troff language.  It finds and runs all
       necessary groff preprocessors, such as chem.

       The groffer program also includes many of the features for
       finding and displaying the Unix manual pages (man pages), such
       that it can be used as a replacement for a man(1) program.
       Moreover, compressed files that can be handled by gzip(1) or
       bzip2(1) are decompressed on-the-fly.

       The normal usage is quite simple by supplying a file name or name
       of a man page without further options.  But the option handling
       has many possibilities for creating special behaviors.  This can
       be done either in configuration files, with the shell environment
       variable GROFFER_OPT, or on the command line.

       The output can be generated and viewed in several different ways
       available for groff.  This includes the X Window System-based
       groff program gxditview(1), each PostScript, PDF, or DVI display
       program, a web browser by generating HTML or XHTML in www mode,
       or several text modes in text terminals.

       Most of the options that must be named when running groff
       directly are determined automatically for groffer, due to the
       internal usage of the grog(1) program.  But all parts can also be
       controlled manually by arguments.

       Several file names can be specified on the command-line
       arguments.  They are transformed into a single document in the
       normal way of groff.

       Option handling is done in GNU style.  Options and file names can
       be mixed freely.  The option “--” closes the option handling, all
       following arguments are treated as file names.  Long options can
       be abbreviated in several ways.

Option Overview         top

       breaking options

               [-h | --help] [-v | --version]

       groffer mode options

               [--auto] [--default] [--default-modes mode1,mode2,...]
               [--dvi] [--groff] [--html] [--latin1]
               [--mode display_mode] [--pdf] [--pdf2] [--ps] [--source]
               [--text] [--to-stdout] [--tty] [--utf8] [--viewer prog]
               [--www] [--xhtml] [--x | --X]

       options related to groff

               [-T | --device device]
               [-Z | --intermediate-output | --ditroff]

              All further groff short options are accepted.

       options for man pages

               [--apropos] [--apropos-data] [--apropos-devel]
               [--apropos-progs] [--man] [--no-man] [--no-special]
               [--whatis]

       long options taken over from GNU man

               [--all] [--ascii] [--ditroff] [--extension suffix]
               [--locale language] [--local-file] [--location | --where]
               [--manpath dir1:dir2:...] [--no-location]
               [--pager program] [--sections sec1:sec2:...]
               [--systems sys1,sys2,...] [--troff-device device]

              Further long options of GNU man are accepted as well.

       options mapped to X Window System Toolkit Intrinsics options

               [--bd | --bordercolor pixels] [--bg | --background color]
               [--bw | --borderwidth pixels] [--display X-display]
               [--fg | --foreground color]
               [--fn | --ft | --font font_name] [--geometry size_pos]
               [--resolution value] [--rv] [--title string]
               [--xrm X-resource]

       options for development

               [--debug] [--debug-filenames] [--debug-grog]
               [--debug-keep] [--debug-params] [--debug-tmpdir]
               [--do-nothing] [--print text] [-V]

       filespec arguments

              The filespec parameters are all arguments that are neither
              an option nor an option argument.  They usually mean a
              file name or a man page searching scheme.

              In the following, the term section_extension is used.  It
              means a word that consists of a man section that is
              optionally followed by an extension.  The name of a man
              section is a single character from [1–9on], the extension
              is some word.  The extension is mostly lacking.

              No filespec parameters means standard input.

              -      stands for standard input (can occur several
                     times).

              filename
                     the path name of an existing file.

              man:name(section_extension)
              man:name.section_extension
              name(section_extension)
              name.section_extension
              section_extension name
                     search the man page name in the section with
                     optional extension section_extension.

              man:name
                     man page in the lowest man section that has name.

              name   if name is not an existing file search for the
                     man page name in the lowest man section.

Option Details         top

       The groffer program can usually be run with very few options.
       But for special purposes, it supports many options.  These can be
       classified in 5 option classes.

       All short options of groffer are compatible with the short
       options of groff(1).  All long options of groffer are compatible
       with the long options of man(1).

       Arguments for long option names can be abbreviated in several
       ways.  First, the argument is checked whether it can be prolonged
       as is.  Furthermore, each minus sign - is considered as a
       starting point for a new abbreviation.  This leads to a set of
       multiple abbreviations for a single argument.  For example,
       --de-n-f can be used as an abbreviation for --debug-not-func, but
       --de-n works as well.  If the abbreviation of the argument leads
       to several resulting options an error is raised.

       These abbreviations are only allowed in the environment variable
       GROFFER_OPT, but not in the configuration files.  In
       configuration, all long options must be exact.

   groffer breaking options
       As soon as one of these options is found on the command line it
       is executed, printed to standard output, and the running groffer
       is terminated thereafter.  All other arguments are ignored.

       -h | --help
              Print help information with a short explanation of options
              to standard output.

       -v | --version
              Print version information to standard output.

   groffer mode options
       The display mode and the viewer programs are determined by these
       options.  If none of these mode and viewer options is specified
       groffer tries to find a suitable display mode automatically.  The
       default modes are mode pdf, mode ps, mode html, mode xhtml, mode
       x, and mode dvi in the X Window System with different viewers and
       mode tty with device utf8 under less on a terminal; other modes
       are tested if the programs for the main default mode do not
       exist.

       In the X Window System, many programs create their own window
       when called.  groffer can run these viewers as an independent
       program in the background.  As this does not work in text mode on
       a terminal (tty) there must be a way to know which viewers are X
       Window System-based graphical programs.  The groffer script has a
       small amount of information on some viewer names.  If a viewer
       argument of the command-line chooses an element that is
       recognized as an X Window System-based program in this list, it
       is treated as a viewer that can run in the background.
       Unrecognized viewers are not run in the background.

       For each mode, you are free to choose whatever viewer you want.
       That need not be some graphical viewer suitable for this mode.
       There is a chance to view the output source; for example, the
       combination of the options --mode=ps and --viewer=less shows the
       content of the PostScript output, the source code, with the pager
       less.

       --auto Equivalent to --mode=auto.

       --default
              Reset all configuration from previously processed command-
              line options to the default values.  This is useful to
              wipe out all former options of the configuration, in
              GROFFER_OPT, and restart option processing using only the
              rest of the command line.

       --default-modes mode1,mode2,...
              Set the sequence of modes for auto mode to the comma
              separated list given in the argument.  See --mode for
              details on modes.  Display in the default manner;
              actually, this means to try the modes x, ps, and tty in
              this sequence.

       --dvi  Equivalent to --mode=dvi.  Known DVI viewers for the X
              Window System include xdvi(1) and dvilx(1).

       --groff
              Equivalent to --mode=groff.

       --html Equivalent to --mode=html.

       --mode value
              Set the display mode.  The following mode values are
              recognized:

              auto   Select the automatic determination of the display
                     mode.  The sequence of modes that are tried can be
                     set with the --default-modes option.  Useful for
                     restoring the default mode when a different mode
                     was specified before.

              dvi    Display formatted input in a DVI viewer program.
                     By default, the formatted input is displayed with
                     the xdvi(1) program.

              groff  After the file determination, switch groffer to
                     process the input like groff(1) would do.  This
                     disables the groffer viewing features.

              html   Translate the input into HTML format and display
                     the result in a web browser program.  By default,
                     the existence of a sequence of standard web
                     browsers is tested, starting with konqueror(1) and
                     mozilla(1).  The text HTML viewer is lynx(1).  By
                     default, the existence of a sequence of standard
                     web browsers is tested, starting with konqueror(1)
                     and mozilla(1).  The text HTML viewer is lynx(1).

              pdf    Transform roff input files into a PDF file by using
                     the groff(1) device -Tpdf.  This is the default PDF
                     generator.  The generated PDF file is displayed
                     with suitable viewer programs, such as okular(1).

              pdf2   This is the traditional pdf mode.  Sometimes this
                     mode produces more correct output than the default
                     PDF mode.  By default, the input is formatted by
                     groff using the PostScript device, then it is
                     transformed into the PDF file format using gs(1),
                     or ps2pdf(1).  If that's not possible, the
                     PostScript mode (ps) is used instead.  Finally it
                     is displayed using different viewer programs.

              ps     Display formatted input in a PostScript viewer
                     program.  By default, the formatted input is
                     displayed in one of many viewer programs.

              text   Format in a groff text mode and write the result to
                     standard output without a pager or viewer program.
                     The text device, latin1 by default, can be chosen
                     with option -T.

              tty    Format in a groff text mode and write the result to
                     standard output using a text pager program, even
                     when in the X Window System.

              www    Equivalent to --mode=html.

              x      Display the formatted input in a native roff
                     viewer.  By default, the formatted input is
                     displayed with the gxditview(1) program being
                     distributed together with groff.  But the legacy X
                     Window System application xditview(1) can also be
                     chosen with the option --viewer.  The default
                     resolution is 75dpi, but 100dpi are also possible.
                     The default groff device for the resolution of
                     75dpi is X75-12, for 100dpi it is X100.  The
                     corresponding groff intermediate output for the
                     actual device is generated and the result is
                     displayed.  For a resolution of 100dpi, the default
                     width of the geometry of the display program is
                     chosen to 850dpi.

              X      Equivalent to --mode=x.

              xhtml  Translate the input into XHTML format, which is an
                     XML version of HTML.  Then display the result in a
                     web browser program, mostly the known HTML viewers.

              The following modes do not use the groffer viewing
              features.  They are only interesting for advanced
              applications.

              groff  Generate device output with plain groff without
                     using the special viewing features of groffer.  If
                     no device was specified by option -T the groff
                     default ps is assumed.

              source Output the roff source code of the input files
                     without further processing.

       --pdf  Equivalent to --mode=pdf.
       --pdf2 Equivalent to --mode=pdf2.

       --ps   Equivalent to --mode=ps.  Common PostScript viewers
              include okular(1), evince(1), gv(1), ghostview(1), and
              gs(1), In each case, arguments can be provided
              additionally.

       --source
              Equivalent to --mode=source.

       --text Equivalent to --mode=text.

       --to-stdout
              The file for the chosen mode is generated and its content
              is printed to standard output.  It will not be displayed
              in graphical mode.

       --tty  Equivalent to --mode=tty.  The standard pager is less(1).
              This option is equivalent to man option --pager=prog.  The
              option argument can be a file name or a program to be
              searched in $PATH; arguments can be provided additionally.

       --viewer prog
              Choose a viewer program for actual device or mode.  This
              can be a file name or a program to be searched in $PATH;
              arguments can be provided additionally.

       --www  Equivalent to --mode=html.

       --X | --x
              Equivalent to --mode=x.  Suitable viewer programs are
              gxditview(1) which is the default and xditview(1).

       --     Signals the end of option processing; all remaining
              arguments are interpreted as filespec parameters.

       Besides these, groffer accepts all short options that are valid
       for the groff(1) program.  All non-groffer options are sent
       unmodified via grog to groff.  So postprocessors, macro packages,
       compatibility with classical troff, and much more can be manually
       specified.

   Options related to groff
       All short options of groffer are compatible with the short
       options of groff(1).  The following of groff options have either
       an additional special meaning within groffer or make sense for
       normal usage.

       Because of the special outputting behavior of the groff option -Z
       groffer was designed to be switched into groff mode; the groffer
       viewing features are disabled there.  The other groff options do
       not switch the mode, but allow to customize the formatting
       process.

       --a    This generates an ASCII approximation of output in the
              text modes.  That could be important when the text pager
              has problems with control sequences in tty mode.

       --m file
              Add file as a groff macro file.  This is useful in case it
              cannot be recognized automatically.

       --P opt_or_arg
              Send the argument opt_or_arg as an option or option
              argument to the actual groff postprocessor.

       --T devname | --device devname
              This option determines groff's output device.  The most
              important devices are the text output devices for
              referring to the different character sets, such as ascii,
              utf8, latin1, utf8, and others.  Each of these arguments
              switches groffer into a text mode using this device, to
              mode tty if the actual mode is not a text mode.  The
              following devname arguments are mapped to the
              corresponding groffer --mode=devname option: dvi, html,
              xhtml, and ps.  All X* arguments are mapped to mode x.
              Each other devname argument switches to mode groff using
              this device.

       --X    is equivalent to groff -X.  It displays the groff
              intermediate output with gxditview.  As the quality is
              relatively bad this option is deprecated; use --X instead
              because the x mode uses an X* device for a better display.

       -Z | --intermediate-output | --ditroff
              Switch into groff mode and format the input with the groff
              intermediate output without postprocessing; see
              groff_out(5).  This is equivalent to option --ditroff of
              man, which can be used as well.

       All other groff options are supported by groffer, but they are
       just transparently transferred to groff without any intervention.
       The options that are not explicitly handled by groffer are
       transparently passed to groff.  Therefore these transparent
       options are not documented here, but in groff(1).  Due to the
       automatism in groffer, none of these groff options should be
       needed, except for advanced usage.

   Options for man pages
       --apropos
              Start the apropos(1) command or facility of man(1) for
              searching the filespec arguments within all man page
              descriptions.  Each filespec argument is taken for search
              as it is; section specific parts are not handled, such
              that 7 groff searches for the two arguments 7 and groff,
              with a large result; for the filespec groff.7 nothing will
              be found.  The language locale is handled only when the
              called programs do support this; the GNU apropos and man
              -k do not.  The display differs from the apropos program
              by the following concepts:

              * Construct a groff frame similar to a man page to the
                output of apropos,

              * each filespec argument is searched on its own.

              * The restriction by --sections is handled as well,

              * wildcard characters are allowed and handled without a
                further option.

       --apropos-data
              Show only the apropos descriptions for data documents,
              these are the man(7) sections 4, 5, and 7.  Direct section
              declarations are ignored, wildcards are accepted.

       --apropos-devel
              Show only the apropos descriptions for development
              documents, these are the man(7) sections 2, 3, and 9.
              Direct section declarations are ignored, wildcards are
              accepted.

       --apropos-progs
              Show only the apropos descriptions for documents on
              programs, these are the man(7) sections 1, 6, and 8.
              Direct section declarations are ignored, wildcards are
              accepted.

       --whatis
              For each filespec argument search all man pages and
              display their description — or say that it is not a
              man page.  This is written from anew, so it differs from
              man's whatis output by the following concepts

              * each retrieved file name is added,

              * local files are handled as well,

              * the language and system locale is supported,

              * the display is framed by a groff output format similar
                to a man page,

              * wildcard characters are allowed without a further
                option.

       The following options were added to groffer for choosing whether
       the file name arguments are interpreted as names for local files
       or as a search pattern for man pages.  The default is looking up
       for local files.

       --man  Check the non-option command-line arguments (filespecs)
              first on being man pages, then whether they represent an
              existing file.  By default, a filespec is first tested
              whether it is an existing file.

       --no-man | --local-file
              Do not check for man pages.  --local-file is the
              corresponding man option.

       --no-special
              Disable former calls of --all, --apropos*, and --whatis.

   Long options taken over from GNU man
       The long options of groffer were synchronized with the long
       options of GNU man.  All long options of GNU man are recognized,
       but not all of these options are important to groffer, so most of
       them are just ignored.  These ignored man options are --catman,
       --troff, and --update.

       In the following, the man options that have a special meaning for
       groffer are documented.

       If your system has GNU man installed the full set of long and
       short options of the GNU man program can be passed via the
       environment variable MANOPT; see man(1).

       --all  In searching man pages, retrieve all suitable documents
              instead of only one.

       -7 | --ascii
              In text modes, display ASCII translation of special
              characters for critical environment.  This is equivalent
              to groff -mtty_char; see groff_tmac(5).

       --ditroff
              Produce groff intermediate output.  This is equivalent to
              groffer -Z.

       --extension suffix
              Restrict man page search to file names that have suffix
              appended to their section element.  For example, in the
              file name /usr/share/man/man3/terminfo.3ncurses.gz the
              man page extension is ncurses.

       --locale language
              Set the language for man pages.  This has the same effect,
              but overwrites $LANG.

       --location
              Print the location of the retrieved files to standard
              error.

       --no-location
              Do not display the location of retrieved files; this
              resets a former call to --location.  This was added by
              groffer.

       --manpath 'dir1:dir2:...'
              Use the specified search path for retrieving man pages
              instead of the program defaults.  If the argument is set
              to the empty string "" the search for man page is
              disabled.

       --pager
              Set the pager program in tty mode; default is less.  This
              can be set with --viewer.

       --sections sec1:sec2:...
              Restrict searching for man pages to the given sections, a
              colon-separated list.

       --systems sys1,sys2,...
              Search for man pages for the given operating systems; the
              argument systems is a comma-separated list.

       --where
              Equivalent to --location.

   X Window System Toolkit Intrinsics options
       The following long options were adapted from the corresponding X
       Window System Toolkit Intrinsics options.  groffer will pass them
       to the actual viewer program if it is an X Window System program.
       Otherwise these options are ignored.

       Unfortunately these options use the old style of a single minus
       for long options.  For groffer that was changed to the standard
       with using a double minus for long options, for example, groffer
       uses the option --font for the X Window System Toolkit Intrinsics
       option -font.

       See X(7) and the manual X Toolkit Intrinsics – C Language
       Interface for more details on these options and their arguments.

       --background color
              Set the background color of the viewer window.

       --bd pixels
              This is equivalent to --bordercolor.

       --bg color
              This is equivalent to --background.

       --bw pixels
              This is equivalent to --borderwidth.

       --bordercolor pixels
              Specifies the color of the border surrounding the viewer
              window.

       --borderwidth pixels
              Specifies the width in pixels of the border surrounding
              the viewer window.

       --display X-display
              Set the X Window System display on which the viewer
              program shall be started.  See section “Display Names” in
              X(7) for the syntax of the argument.

       --foreground color
              Set the foreground color of the viewer window.

       --fg color
              This is equivalent to --foreground.

       --fn font_name
              This is equivalent to --font.

       --font font_name
              Set the font used by the viewer window.  The argument is
              an X Window System font name.

       --ft font_name
              This is equivalent to --font.

       --geometry size_pos
              Set the geometry of the display window, that means its
              size and its starting position.  See section “Geometry
              Specifications” in X(7) for the syntax of the argument.

       --resolution value
              Set X Window System resolution in dpi (dots per inch) in
              some viewer programs.  The only supported dpi values are
              75 and 100.  Actually, the default resolution for groffer
              is set to 75dpi.  The resolution also sets the default
              device in mode x.

       --rv   Reverse foreground and background color of the viewer
              window.

       --title 'some text'
              Set the title for the viewer window.

       --xrm 'resource'
              Set the X Window System server resource to the given
              value.

   Options for development
       --debug
              Enable all debugging options --debug-type.  The temporary
              files are kept and not deleted, the grog output is
              printed, the name of the temporary directory is printed,
              the displayed file names are printed, and the parameters
              are printed.

       --debug-filenames
              Print the names of the files and man pages that are
              displayed by groffer.

       --debug-grog
              Print the output of all grog commands.

       --debug-keep
              Enable two debugging informations.  Print the name of the
              temporary directory and keep the temporary files, do not
              delete them during the run of groffer.

       --debug-params
              Print the parameters, as obtained from the configuration
              files, from GROFFER_OPT, and the command-line arguments.

       --debug-tmpdir
              Print the name of the temporary directory.

       --do-nothing
              This is like --version, but without the output; no viewer
              is started.  This makes only sense in development.

       --print=text
              Just print the argument to standard error.  This is good
              for parameter check.

       -V     This is an advanced option for debugging only.  Instead of
              displaying the formatted input, a lot of groffer specific
              information is printed to standard output:

              * the output file name in the temporary directory,

              * the display mode of the actual groffer run,

              * the display program for viewing the output with its
                arguments,

              * the active parameters from the config files, the
                arguments in GROFFER_OPT, and the arguments of the
                command line,

              * the pipeline that would be run by the groff program, but
                without executing it.

       Other useful debugging options are the groff option -Z and
       --mode=groff.

   Filespec arguments
       A filespec parameter is an argument that is not an option or
       option argument.  In groffer, filespec parameters are a file name
       or a template for searching man pages.  These input sources are
       collected and composed into a single output file such as groff
       does.

       The strange POSIX behavior to regard all arguments behind the
       first non-option argument as filespec arguments is ignored.  The
       GNU behavior to recognize options even when mixed with filespec
       arguments is used throughout.  But, as usual, the double minus
       argument -- ends the option handling and interprets all following
       arguments as filespec arguments; so the POSIX behavior can be
       easily adopted.

       The options --apropos* have a special handling of filespec
       arguments.  Each argument is taken as a search scheme of its own.
       Also a regexp (regular expression) can be used in the filespec.
       For example, groffer --apropos '^gro.f$' searches groff in the
       man page name, while groffer --apropos groff searches groff
       somewhere in the name or description of the man pages.

       All other parts of groffer, such as the normal display or the
       output with --whatis have a different scheme for filespecs.  No
       regular expressions are used for the arguments.  The filespec
       arguments are handled by the following scheme.

       It is necessary to know that on each system the man pages are
       sorted according to their content into several sections.  The
       classical man sections have a single-character name, either a
       digit from 1 to 9 or one of the characters n or o.

       This can optionally be followed by a string, the so-called
       extension.  The extension allows the storage of several man pages
       with the same name in the same section.  But the extension is
       only rarely used; usually it is omitted.  Then the extensions are
       searched automatically by alphabet.

       In the following, we use the name section_extension for a word
       that consists of a single character section name or a section
       character that is followed by an extension.  Each filespec
       parameter can have one of the following forms in decreasing
       sequence.

       * No filespec parameters means that groffer waits for standard
         input.  The minus option - always stands for standard input; it
         can occur several times.  If you want to look up a man page
         called - use the argument man:-.

       * Next a filespec is tested whether it is the path name of an
         existing file.  Otherwise it is assumed to be a searching
         pattern for a man page.

       * man:name(section_extension), man:name.section_extension,
         name(section_extension), or name.section_extension search the
         man page name in man section and possibly extension of
         section_extension.

       * Now man:name searches for a man page in the lowest man section
         that has a document called name.

       * section_extension name is a pattern of 2 arguments that
         originates from a strange argument parsing of the man program.
         Again, this searches the man page name with section_extension,
         a combination of a section character optionally followed by an
         extension.

       * We are left with the argument name which is not an existing
         file.  So this searches for the man page called name in the
         lowest man section that has a document for this name.

       Several file name arguments can be supplied.  They are mixed by
       groff into a single document.  Note that the set of option
       arguments must fit to all of these file arguments.  So they
       should have at least the same style of the groff language.

Output Modes         top

       By default, the groffer program collects all input into a single
       file, formats it with the groff program for a certain device, and
       then chooses a suitable viewer program.  The device and viewer
       process in groffer is called a mode.  The mode and viewer of a
       running groffer program is selected automatically, but the user
       can also choose it with options.  The modes are selected by
       option the arguments of --mode=anymode.  Additionally, each of
       this argument can be specified as an option of its own, such as
       anymode.  Most of these modes have a viewer program, which can be
       chosen by the option --viewer.

       Several different modes are offered: graphical modes for the X
       Window System, text modes, and some direct groff modes for
       debugging and development.

       By default, groffer first tries whether x mode is possible, then
       ps mode, and finally tty mode.  This mode testing sequence for
       auto mode can be changed by specifying a comma separated list of
       modes with the option --default-modes.

       The searching for man pages and the decompression of the input
       are active in every mode.

   Graphical display modes
       The graphical display modes work mostly in the X Window System
       environment (or similar implementations within other windowing
       environments).  The environment variable DISPLAY and the option
       --display are used for specifying the X Window System display to
       be used.  If this environment variable is empty, groffer assumes
       that the X Window System is not running and changes to a
       text mode.  You can change this automatic behavior by the option
       --default-modes.

       Known viewers for the graphical display modes and their standard
       X Window System viewer programs are

       * in a PDF viewer (pdf mode)

       * in a web browser (html, xhtml, or www mode)

       * in a PostScript viewer (ps mode)

       * X Window System roff viewers such as gxditview(1) or
         xditview(1) (in x mode)

       * in a DVI viewer program (dvi mode)

       The pdf mode has a major advantage — it is the only graphical
       display mode that allows searching for text within the viewer;
       this can be a really important feature.  Unfortunately, it takes
       some time to transform the input into the PDF format, so it was
       not chosen as the major mode.

       These graphical viewers can be customized by options of the X
       Window System Toolkit Intrinsics.  But the groffer options use a
       leading double minus instead of the single minus used by the X
       Window System Toolkit Intrinsics.

   Text modes
       There are two modes for text output, mode text for plain output
       without a pager and mode tty for a text output on a text terminal
       using some pager program.

       If the variable DISPLAY is not set or empty, groffer assumes that
       it should use tty mode.

       In the actual implementation, the groff output device latin1 is
       chosen for text modes.  This can be changed by specifying option
       -T or --device.

       The pager to be used can be specified by one of the options
       --pager and --viewer, or by the environment variable PAGER.  If
       all of this is not used the less(1) program with the option -r
       for correctly displaying control sequences is used as the default
       pager.

   Special modes for debugging and development
       These modes use the groffer file determination and decompression.
       This is combined into a single input file that is fed directly
       into groff with different strategy without the groffer viewing
       facilities.  These modes are regarded as advanced, they are
       useful for debugging and development purposes.

       The source mode with option --source just displays the
       decompressed input.

       Option --to-stdout does not display in a graphical mode.  It just
       generates the file for the chosen mode and then prints its
       content to standard output.

       The groff mode passes the input to groff using only some suitable
       options provided to groffer.  This enables the user to save the
       generated output into a file or pipe it into another program.

       In groff mode, the option -Z disables post-processing, thus
       producing the groff intermediate output.  In this mode, the input
       is formatted, but not postprocessed; see groff_out(5) for
       details.

       All groff short options are supported by groffer.

Man Page Searching         top

       The default behavior of groffer is to first test whether a file
       parameter represents a local file; if it is not an existing file
       name, it is assumed to represent the name of a man page.  The
       following options can be used to determine whether the arguments
       should be handled as file name or man page arguments.

       --man  forces to interpret all file parameters as filespecs for
              searching man pages.

       --no-man
       --local-file
              disable the man searching; so only local files are
              displayed.

       If neither a local file nor a man page was retrieved for some
       file parameter a warning is issued on standard error, but
       processing is continued.

   Search algorithm
       Let us now assume that a man page should be searched.  The
       groffer program provides a search facility for man pages.  All
       long options, all environment variables, and most of the
       functionality of the GNU man(1) program were implemented.  The
       search algorithm shall determine which file is displayed for a
       given man page.  The process can be modified by options and
       environment variables.

       The only man action that is omitted in groffer are the
       preformatted man pages, also called cat pages.  With the
       excellent performance of the actual computers, the preformatted
       man pages aren't necessary any longer.  Additionally, groffer is
       a roff program; it wants to read roff source files and format
       them itself.

       The algorithm for retrieving the file for a man page needs first
       a set of directories.  This set starts with the so-called
       man path that is modified later on by adding names of operating
       system and language.  This arising set is used for adding the
       section directories which contain the man page files.

       The man path is a list of directories that are separated by
       colon.  It is generated by the following methods.

       * The environment variable MANPATH can be set.

       * It can be read from the arguments of the environment variable
         MANOPT.

       * The man path can be manually specified by using the option
         --manpath.  An empty argument disables the man page searching.

       * When no man path was set the manpath(1) program is tried to
         determine one.

       * If this does not work a reasonable default path from $PATH is
         determined.

       We now have a starting set of directories.  The first way to
       change this set is by adding names of operating systems.  This
       assumes that man pages for several operating systems are
       installed.  This is not always true.  The names of such operating
       systems can be provided by 3 methods.

       * The environment variable SYSTEM has the lowest precedence.

       * This can be overridden by an option in MANOPT.

       * This again is overridden by the command-line option --systems.

       Several names of operating systems can be given by appending
       their names, separated by a comma.

       The man path is changed by appending each system name as
       subdirectory at the end of each directory of the set.  No
       directory of the man path set is kept.  But if no system name is
       specified the man path is left unchanged.

       After this, the actual set of directories can be changed by
       language information.  This assumes that there exist man pages in
       different languages.  The wanted language can be chosen by
       several methods.

       * Environment variable LANG.

       * This is overridden by LC_MESSAGES.

       * This is overridden by LC_ALL.

       * This can be overridden by providing an option in MANOPT.

       * All these environment variables are overridden by the command-
         line option --locale.

       The default language can be specified by specifying one of the
       pseudo-language parameters C or POSIX.  This is like deleting a
       formerly given language information.  The man pages in the
       default language are usually in English.

       Of course, the language name is determined by man.  In GNU man,
       it is specified in the POSIX 1003.1 based format:

       <language>[_<territory>[.<character-set>[,<version>]]],

       but the two-letter code in <language> is sufficient for most
       purposes.  If for a complicated language formulation no man pages
       are found groffer searches the country part consisting of these
       first two characters as well.

       The actual directory set is copied thrice.  The language name is
       appended as subdirectory to each directory in the first copy of
       the actual directory set (this is only done when a language
       information is given).  Then the 2-letter abbreviation of the
       language name is appended as subdirectories to the second copy of
       the directory set (this is only done when the given language name
       has more than 2 letters).  The third copy of the directory set is
       kept unchanged (if no language information is given this is the
       kept directory set).  These maximally 3 copies are appended to
       get the new directory set.

       We now have a complete set of directories to work with.  In each
       of these directories, the man files are separated in sections.
       The name of a section is represented by a single character, a
       digit between 1 and 9, or the character o or n, in this order.

       For each available section, a subdirectory man<section> exists
       containing all man files for this section, where <section> is a
       single character as described before.  Each man file in a section
       directory has the form
       man<section>/<name>.<section>[<extension>][.<compression>], where
       <extension> and <compression> are optional.  <name> is the name
       of the man page that is also specified as filespec argument on
       the command line.

       The extension is an addition to the section.  This postfix acts
       like a subsection.  An extension occurs only in the file name,
       not in name of the section subdirectory.  It can be specified on
       the command line.

       On the other hand, the compression is just an information on how
       the file is compressed.  This is not important for the user, such
       that it cannot be specified on the command line.

       There are 4 methods to specify a section on the command line:

       * Environment variable MANSECT

       * Command-line option --sections

       * Appendix to the name argument in the form <name>.<section>

       * Preargument before the name argument in the form <section>
         <name>

       It is also possible to specify several sections by appending the
       single characters separated by colons.  One can imagine that this
       means to restrict the man page search to only some sections.  The
       multiple sections are only possible for MANSECT and --sections.

       If no section is specified all sections are searched one after
       the other in the given order, starting with section 1, until a
       suitable file is found.

       There are 4 methods to specify an extension on the command line.
       But it is not necessary to provide the whole extension name, some
       abbreviation is good enough in most cases.

       * Environment variable EXTENSION

       * Command-line option --extension

       * Appendix to the <name>.<section> argument in the form
         <name>.<section><extension>

       * Preargument before the name argument in the form
         <section><extension> <name>

       For further details on man page searching, see man(1).

   Examples of man files
       /usr/share/man/man1/groff.1
              This is an uncompressed file for the man page groff in
              section 1.  It can be called by
              sh# groffer groff
              No section is specified here, so all sections should be
              searched, but as section 1 is searched first this file
              will be found first.  The file name is composed of the
              following components.  /usr/share/man/ must be part of the
              man path; the subdirectory man1/ and the part .1 stand for
              the section; groff is the name of the man page.

       /usr/local/share/man/man7/groff.7.gz
              The file name is composed of the following components.
              /usr/local/share/man must be part of the man path; the
              subdirectory man7/ and the part .7 stand for the section;
              groff is the name of the man page; the final part .gz
              stands for a compression with gzip(1).  As the section is
              not the first one it must be specified as well.  This can
              be done by one of the following commands.
              sh# groffer groff.7
              sh# groffer 7 groff
              sh# groffer --sections=7 groff

       /usr/local/man/man1/ctags.1emacs21.bz2
              Here /usr/local/man must be in man path; the subdirectory
              man1/ and the file name part .1 stand for section 1; the
              name of the man page is ctags; the section has an
              extension emacs21; and the file is compressed as .bz2 with
              bzip2(1).  The file can be viewed with one of the
              following commands
              sh# groffer ctags.1e
              sh# groffer 1e ctags
              sh# groffer --extension=e --sections=1 ctags
              where e works as an abbreviation for the extension
              emacs21.

       /usr/man/linux/de/man7/man.7.Z
              The directory /usr/man is now part of the man path; then
              there is a subdirectory for an operating system name
              linux/; next comes a subdirectory de/ for the German
              language; the section names man7 and .7 are known so far;
              man is the name of the man page; and .Z signifies the
              compression that can be handled by gzip(1).  We want now
              show how to provide several values for some options.  That
              is possible for sections and operating system names.  So
              we use as sections 5 and 7 and as system names linux and
              aix.  The command is then

              sh# groffer --locale=de --sections=5:7 --systems=linux,aix man
              sh# LANG=de MANSECT=5:7 SYSTEM=linux,aix groffer man

Decompression         top

       The program has a decompression facility.  If standard input or a
       file that was retrieved from the command line parameters is
       compressed with a format that is supported by either gzip(1) or
       bzip2(1) it is decompressed on-the-fly.  This includes the GNU
       .gz, .bz2, and the traditional .Z compression.  The program
       displays the concatenation of all decompressed input in the
       sequence that was specified on the command line.

Environment         top

       The groffer program supports many system variables, most of them
       by courtesy of other programs.  All environment variables of
       groff(1) and GNU man(1) and some standard system variables are
       honored.

   Native groffer variables
       GROFFER_OPT
              Store options for a run of groffer.  The options specified
              in this variable are overridden by the options given on
              the command line.  The content of this variable is run
              through the shell builtin “eval”, so arguments containing
              whitespace or special shell characters should be quoted.
              Do not forget to export this variable, otherwise it does
              not exist during the run of groffer.

   System variables
       The following variables have a special meaning for groffer.

       DISPLAY
              If set, this variable indicates that the X Window System
              is running.  Testing this variable decides on whether
              graphical or text output is generated.  This variable
              should not be changed by the user carelessly, but it can
              be used to start the graphical groffer on a remote X
              Window System terminal.  For example, depending on your
              system, groffer can be started on the second monitor by
              the command

              sh# DISPLAY=:0.1 groffer what.ever &

       LC_ALL
       LC_MESSAGES
       LANG   If one of these variables is set (in the above sequence),
              its content is interpreted as the locale, the language to
              be used, especially when retrieving man pages.  A locale
              name is typically of the form
              language[_territory[.codeset[@modifier]]], where language
              is an ISO 639 language code, territory is an ISO 3166
              country code, and codeset is a character set or encoding
              identifier like ISO-8859-1 or UTF-8; see setlocale(3).
              The locale values C and POSIX stand for the default, i.e.
              the man page directories without a language prefix.  This
              is the same behavior as when all 3 variables are unset.

       PAGER  This variable can be used to set the pager for the tty
              output.  For example, to disable the use of a pager
              completely set this variable to the cat(1) program

              sh# PAGER=cat groffer anything

       PATH   All programs within the groffer script are called without
              a fixed path.  Thus this environment variable determines
              the set of programs used within the run of groffer.

   groff variables
       The groffer program internally calls groff, so all environment
       variables documented in groff(1) are internally used within
       groffer as well.  The following variable has a direct meaning for
       the groffer program.

       GROFF_TMPDIR
              If the value of this variable is an existing, writable
              directory, groffer uses it for storing its temporary
              files, just as groff does.  See the groff(1) man page for
              more details on the location of temporary files.

   man variables
       Parts of the functionality of the man program were implemented in
       groffer; support for all environment variables documented in
       man(1) was added to groffer, but the meaning was slightly
       modified due to the different approach in groffer; but the user
       interface is the same.  The man environment variables can be
       overwritten by options provided with MANOPT, which in turn is
       overwritten by the command line.

       EXTENSION
              Restrict the search for man pages to files having this
              extension.  This is overridden by option --extension; see
              there for details.

       MANOPT This variable contains options as a preset for man(1).  As
              not all of these are relevant for groffer only the
              essential parts of its value are extracted.  The options
              specified in this variable overwrite the values of the
              other environment variables that are specific to man.  All
              options specified in this variable are overridden by the
              options given on the command line.

       MANPATH
              If set, this variable contains the directories in which
              the man page trees are stored.  This is overridden by
              option --manpath.

       MANSECT
              If this is a colon separated list of section names, the
              search for man pages is restricted to those manual
              sections in that order.  This is overridden by option
              --sections.

       SYSTEM If this is set to a comma separated list of names these
              are interpreted as man page trees for different operating
              systems.  This variable can be overwritten by option
              --systems; see there for details.

       The environment variable MANROFFSEQ is ignored by groffer because
       the necessary preprocessors are determined automatically.

Configuration Files         top

       The groffer program can be preconfigured by two configuration
       files.

       /etc/groff/groffer.conf
              System-wide configuration file for groffer.

       $HOME/.groff/groffer.conf
              User-specific configuration file for groffer, where $HOME
              denotes the user's home directory.  This file is called
              after the system-wide configuration file to enable
              overriding by the user.

       Both files are handled for the configuration, but the
       configuration file in /etc comes first; it is overwritten by the
       configuration file in the home directory; both configuration
       files are overwritten by the environment variable GROFFER_OPT;
       everything is overwritten by the command-line arguments.

       The configuration files contain options that should be called as
       default for every groffer run.  These options are written in
       lines such that each contains either a long option, a short
       option, or a short option cluster; each with or without an
       argument.  So each line with configuration information starts
       with a minus character “-”; a line with a long option starts with
       two minus characters “--”, a line with a short option or short
       option cluster starts with a single minus “-”.

       The option names in the configuration files may not be
       abbreviated, they must be exact.

       The argument for a long option can be separated from the option
       name either by an equal sign “=” or by whitespace, i.e. one or
       several space or tab characters.  An argument for a short option
       or short option cluster can be directly appended to the option
       name or separated by whitespace.  The end of an argument is the
       end of the line.  It is not allowed to use a shell environment
       variable in an option name or argument.

       It is not necessary to use quotes in an option or argument,
       except for empty arguments.  An empty argument can be provided by
       appending a pair of quotes to the separating equal sign or
       whitespace; with a short option, the separator can be omitted as
       well.  For a long option with a separating equal sign “=”, the
       pair of quotes can be omitted, thus ending the line with the
       separating equal sign.  All other quote characters are cancelled
       internally.

       In the configuration files, arbitrary whitespace is allowed at
       the beginning of each line, it is just ignored.  Each whitespace
       within a line is replaced by a single space character “ ”
       internally.

       All lines of the configuration lines that do not start with a
       minus character are ignored, such that comments starting with “#”
       are possible.  So there are no shell commands in the
       configuration files.

       As an example, consider the following configuration file that can
       be used either in /etc/groff/groffer.conf or
       ~/.groff/groffer.conf .

       # groffer configuration file
       #
       # groffer options that are used in each call of groffer
       --foreground=DarkBlue
       --resolution=100
       --viewer=gxditview -geometry 900x1200

       The lines starting with # are just ignored, so they act as
       command lines.  This configuration sets four groffer options (the
       lines starting with “-”).  This has the following effects:

       * Use a text color of DarkBlue in all viewers that support this,
         such as gxditview.

       * Use a resolution of 100dpi in all viewers that support this,
         such as gxditview.  By this, the default device in x mode is
         set to X100.

       * Force gxditview(1) as the x-mode viewer using the geometry
         option for setting the width to 900px and the height to 1200px.
         This geometry is suitable for a resolution of 100dpi.

       * Use xpdf(1) as the pdf-mode viewer with the argument -Z 150.

Example         top

       The usage of groffer is very easy.  Usually, it is just called
       with a file name or man page.  The following examples, however,
       show that groffer has much more fancy capabilities.

       sh# groffer /usr/local/share/doc/groff/meintro.ms.gz

       Decompress, format and display the compressed file meintro.ms.gz
       in the directory /usr/local/share/doc/groff, using the standard
       viewer gxditview as graphical viewer when in the X Window System,
       or the less(1) pager program otherwise.

       sh# groffer groff

       If the file ./groff exists use it as input.  Otherwise interpret
       the argument as a search for the man page named groff in the
       smallest possible man section, being section 1 in this case.

       sh# groffer man:groff

       search for the man page of groff even when the file ./groff
       exists.

       sh# groffer groff.7
       sh# groffer 7 groff

       search the man page of groff in man section 7.  This section
       search works only for a digit or a single character from a small
       set.

       sh# groffer fb.modes

       If the file ./fb.modes does not exist interpret this as a search
       for the man page of fb.modes.  As the extension modes is not a
       single character in classical section style the argument is not
       split to a search for fb.

       sh# groffer groff ’troff(1)’ man:roff

       The arguments that are not existing files are looked-up as the
       following man pages: groff (automatic search, should be found in
       man section 1), troff (in section 1), and roff (in the section
       with the lowest number, being 7 in this case).  The quotes around
       ’troff(1)’ are necessary because the parentheses are special
       shell characters; escaping them with a backslash character \( and
       \) would be possible, too.  The formatted files are concatenated
       and displayed in one piece.

       sh# LANG=de groffer --man --viewer=galeon ls

       Retrieve the German man page (language de) for the ls program,
       decompress it, format it to html or xhtml format (www mode) and
       view the result in the web browser galeon.  The option --man
       guarantees that the man page is retrieved, even when a local file
       ls exists in the actual directory.

       sh# groffer --source 'man:roff(7)'

       Get the man page called roff in man section 7, decompress it, and
       print its unformatted content, its source code.

       sh# groffer --de-p --in --ap

       This is a set of abbreviated arguments, it is determined as

       sh# groffer --debug-params --intermediate-output --apropos

       sh# cat file.gz | groffer -Z -mfoo

       The file file.gz is sent to standard input, this is decompressed,
       and then this is transported to the groff intermediate output
       mode without post-processing (groff option -Z), using macro
       package foo (groff option -m).

       sh# echo '\f(CBWOW!' |
       > groffer --x --bg red --fg yellow --geometry 200x100 -

       Display the word WOW! in a small window in constant-width bold
       font, using color yellow on red background.

Compatibility         top

       The groffer program is written in Perl, the Perl version during
       writing was v5.8.8.

       groffer provides its own parser for command-line arguments that
       is compatible to both POSIX getopts(1) and GNU getopt(1).  It can
       handle option arguments and file names containing white space and
       a large set of special characters.  The following standard types
       of options are supported.

       * The option consisting of a single minus - refers to standard
         input.

       * A single minus followed by characters refers to a single
         character option or a combination thereof; for example, the
         groffer short option combination -Qmfoo is equivalent to
         -Q -m foo.

       * Long options are options with names longer than one character;
         they are always preceded by a double minus.  An option argument
         can either go to the next command-line argument or be appended
         with an equal sign to the argument; for example, --long=arg is
         equivalent to --long arg.

       * An argument of -- ends option parsing; all further command-line
         arguments are interpreted as filespec parameters, i.e. file
         names or constructs for searching man pages).

       * All command-line arguments that are neither options nor option
         arguments are interpreted as filespec parameters and stored
         until option parsing has finished.  For example, the command
         line

         sh# groffer file1 -a -o arg file2

         is equivalent to

         sh# groffer -a -o arg -- file1 file2

       The free mixing of options and filespec parameters follows the
       GNU principle.  That does not fulfill the strange option behavior
       of POSIX that ends option processing as soon as the first non-
       option argument has been reached.  The end of option processing
       can be forced by the option “--” anyway.

Authors         top

       groffer was written by Bernd Warken ⟨groff-bernd.warken-72@
       web.de⟩.

See Also         top

       groff(1), troff(1)
              Details on the options and environment variables available
              in groff; all of them can be used with groffer.

       grog(1)
              This program tries to guess the necessary groff command-
              line options from the input and the groffer options.

       groff(7)
              Documentation of the groff language.

       groff_char(7)
              Documentation on the groff characters, special characters,
              and glyphs..

       groff_tmac(5)
              Documentation on the groff macro files.

       groff_out(5)
              Documentation on the groff intermediate output before the
              run of a postprocessor.  (ditroff output).  This can be
              run by the groff or groffer option -Z.

       man(1) The standard program to display man pages.  The
              information there is only useful if it is the man page for
              GNU man.  Then it documents the options and environment
              variables that are supported by groffer.

       gxditview(1)
       xditview(1x)
              Viewers for groffer's x mode.

       kpdf(1)
       kghostview(1)
       evince(1)
       ggv(1)
       gv(1)
       ghostview(1)
       gs(1)  Viewers for groffer's ps mode.

       kpdf(1)
       acroread(1)
       evince(1)
       xpdf(1)
       gpdf(1)
       kghostview(1)
       ggv(1) Viewers for groffer's pdf mode.

       kdvi(1), xdvi(1), dvilx(1)
              Viewers for groffer's dvi mode.

       konqueror(1)
       epiphany(1)
       firefox(1)
       mozilla(1)
       netscape(1)
       lynx(1)
              Web-browsers for groffer's html, xhtml, or www mode.

       less(1)
       more(1)
              Standard pager program for the tty mode.

       gzip(1)
       bzip2(1)
       xz(1)  The decompression programs supported by groffer.

COLOPHON         top

       This page is part of the groff (GNU troff) project.  Information
       about the project can be found at 
       ⟨http://www.gnu.org/software/groff/⟩.  If you have a bug report
       for this manual page, see ⟨http://www.gnu.org/software/groff/⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://git.savannah.gnu.org/git/groff.git⟩ on 2020-12-18.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2020-12-09.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

groff 1.22.4.12-7f8a         30 January 2020                  groffer(1)

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