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groffer - Unix, Linux Command
NAMEgroffer - display groff files and man~pages on X and tty
SYNOPSIS@1] [option...] [filespecEllipsis]]
DESCRIPTIONThe groffer program is the easiest way to use groff(1). It can display arbitrary documents written in the groff(7) language or other roff(7) languages that are compatible to the original troff language. 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 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 groff native X viewer gxditview(1), each Postcript or dvi display program, a web browser by generating html 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.
|groffer mode options|
|options related to groff|
All further groff short options are accepted.
|X Window toolkit options|
|options from man|
Further long options of GNU man are accepted as well.
No filespec parameters means standard input.
OPTION DETAILSThe 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).
groffer breaking OptionsAs 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.
|Start the apropos(1) command for searching within man page descriptions. That slightly differs from the strange behavior of the program of man(1), which has no argument of its own, but takes the file arguments instead. Practically both concepts are compatible.|
|Show only the apropos(1) descriptions for data documents, in the man(7) sections 4, 5, and 7.|
|Show only the apropos(1) descriptions for development documents, in the man(7) sections 2, 3, and 9.|
|Show only the apropos(1) descriptions for documents on programs, in the man(7) sections 1, 6, and 8.|
|Print a helping information with a short explanation of option sto standard output.|
|Print version information to standard output.|
groffer Mode OptionsThe 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.
|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 and restart option processing using only the rest of the command line.|
|Set the sequence of modes for auto mode to the comma separated list given in the argument. See for details on modes. Display in the default manner; actually, this means to try the modes x, ps, and tty in this sequence.|
|Set the viewer program for dvi mode. This can be a file name or a program to be searched in Known dvi viewers inlude xdvi(1) and dvilx(1) In each case, arguments can be provided additionally.|
Set the display mode.
The following mode values are recognized:
|Set the viewer program for pdf mode. This can be a file name or a program to be searched in In each case, arguments can be provided additionally.|
|Set the viewer program for ps mode. This can be a file name or a program to be searched in Common Postscript viewers inlude gv(1), ghostview(1), and gs(1), In each case, arguments can be provided additionally.|
|Choose tty display mode, that means displaying in a text pager even when in X; eqivalent to|
|Set the web browser program for viewing in www mode. Each program that accepts html input and allows the file://localhost/dir/file syntax on the command line is suitable as viewer program; it can be the path name of an executable file or a program in In each case, arguments can be provided additionally.|
|Set the viewer program for x mode. Suitable viewer programs are gxditview(1) and xditview(1). But the argument can be any executable file or a program in In each case, arguments can be provided additionally.|
|Signals the end of option processing; all remaining arguments are interpreted as filespec parameters.|
Options for Development
|Print debugging information for development only. Actually, a function call stack is printed if an error occurs.|
|Specify the shell under which the groffer script should be run. The script first tests whether this option is set (either by configuration, within or as a command line option); if so, the script is rerun under the shell program specified with the option argument.|
|Output the roff source code of the input files without further processing. This is the equivalent|
Options related to groffAll 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 options and groffer was designed to be switched into groff mode by these; the groffer viewing features are disabled there. The other groff options do not switch the mode, but allow to customize the formatting process.
|This generates an ascii approximation of output in text modes. That could be important when the text pager has problems with control sequences.|
|Add file as a groff macro file. This is useful in case it cannot be recognized automatically.|
|Send the argument opt_or_arg as an option or option argument to the actual groff postprocessor.|
|This option determines groffs output device. The most important devices are the text output devices for referring to the different character sets, such as ascii, utf8, latin1, 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 option: dvi, html, and ps. All X* arguments are mapped to mode X. Each other devname argument switches to mode groff using this device.|
|Switch into groff mode and show only the groff calling pipe without formatting the input. This an advanced option from groff(1) , only useful for debugging.|
|was made equivalent to this slightly enhances the facility of groffs option.|
|Switch into groff mode and format the input with groff intermediate output without postprocessing; see groff_out(1). This is equivalent to option of man, which can be used as well.|
X Window toolkit OptionsThe following long options were adapted from the corresponding X Toolkit options. groffer will pass them to the actual viewer program if it is an X Window 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 for the X option
See X(1), X(7), and the documentation on the X toolkit options for more details on these options and their arguments.
|Set the background color of the viewer window.|
|Specifies the color of the border surrounding the viewer window.|
|This is equivalent to|
|Specifies the width in pixels of the border surrounding the viewer window.|
|Set the X display on which the viewer program shall be started, see the X Window documentation for the syntax of the argument.|
|Set the foreground color of the viewer window.|
|This is equivalent to|
|Set the font used by the viewer window. The argument is an X font name.|
|This is equivalent to|
|Set the geometry of the display window, that means its size and its starting position. See X(7) for the syntax of the argument.|
|Set X 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 75.|
|Reverse foreground and background color of the viewer window.|
|Set the title for the viewer window.|
|Set X resource.|
Options from manThe long options of groffer were synchronized with the long options of GNUman. 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.
The following two options were added by 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.
|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.|
|Do not check for man~pages. is the corresponding man option.|
The full set of long and short options of the GNU man program can be passed via the environment variable see man(1) if your system has GNU man installed.
|In searching man~pages, retrieve all suitable documents instead of only one.|
|In text modes, display ASCII translation of special characters.|
|Eqivalent to groffer|
|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.|
|Set the language for man pages. This has the same effect, but overwrites|
|Print the location of the retrieved files to standard error.|
|Do not display the location of retrieved files; this resets a former call to This was added by groffer.|
|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.|
|Set the pager program in tty mode; default is less. This is equivalent to|
|Restrict searching for man~pages to the given sections, a colon-separated list.|
|Search for man pages for the given operating systems; the argument systems is a comma-separated list.|
|Instead of displaying the content, get the one-liner description from the retrieved man~page files [em] or say that it is not a man~page.|
Filespec ArgumentsA filespec parameter is an argument meaning an input source, such as a file name or 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 that maps all arguments behind the first non-option argument into filespec arguments is ignored. The GNU behavior to recognize options even when mixed with filespec arguments is used througout. But, as usual, the double minus argument still takes all following arguments as filespecs.
Each filespec parameters can have one of the following forms.
No filespec parameters means that groffer waits for standard input. The minus option stands for standard input, too, but can occur several times. Next filespec is tested whether it is the path name of an existing file. Otherwise it is assumed as a searching pattern for a man~page.
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 are a digit from 1 to 9 or one of the characters n or o. In the following, a stand-alone character s means this scheme.
The internal precedence of man for searching man pages with the same name within several sections goes according to the classical single-character sequence. On some systems, this single character can be extended by a following string. But the special groffer man page facility is based on the classical single character sections.
man:name(section) and name(section) search the man~page name in man~section~ section, where section can be any string, but it must exist in the man system.
Next some patterns based on the classical man sections were constructed. man:name.s and name.s search for a man~page name in man~section s if s is a classical man section mentioned above. Otherwise search for a man~page named name.s in the lowest man section.
Now man:name searches for a man~page in the lowest man~section that has a document called name.
The pattern s name originates from a strange argument parsing of the man program. If s is a classical man section interpret it as a search for a man~page called name in man~section s, otherwise interpret s as a file argument and name as another filespec argument.
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 MODESBy 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 Additionally, each of this argument can be specified as an option of its own, such as Most of these modes have a viewer program, which can be chosen by an option that is constructed like
Several different modes are offered, graphical X modes, 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
The searching for man~pages and the decompression of the input are active in every mode.
Graphical Display ModesThe graphical display modes work only in the X Window environment (or similar implementations within other windowing environments). The environment variable and the option are used for specifying the X display to be used. If neither is given, groffer assumes that no X and changes to one text mode. You can change this automatic behavior by the option
Known viewers for the graphical display modes and their standard X Window viewer progams are
|X Window roff viewers such as gxditview(1) or xditview(1) (in x or X mode),|
|in a Postscript viewer (ps mode),|
|in a dvi viewer program (dvi mode),|
|in a PDF viewer (pdf mode),|
|in a web browser (html or www mode),|
The pdf mode has a major advantage [em] it is the only graphical diplay mode that allows to search 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 Toolkit. But the groffer options use a leading double minus instead of the single minus used by the X Window Toolkit.
Text modeThere are to 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 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 or
The pager to be used can be specified by one of the options
or by the environment variable
If all of this is not used the
program with the option
for correctly displaying control sequences is used as the default
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 just displays the generated input. 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 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~SEARCHINGThe 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 a name of a man~page. This behavior can be modified by the following options.
|forces to interpret all file parameters as filespecs for searching man~pages.|
||disable the man searching; so only local files are displayed.|
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. This inludes the extended file names of man~pages, for example, the man~page of groff in man~section 7 may be stored under where is part of the man~path, the subdirectory man7 and the file extension .7 refer to the man~section 7; .gz shows the compression of the file.
The cat~pages (preformatted man~pages) are intentionally excluded from the search because groffer is a roff program that wants to format by its own. With the excellent performance of the actual computers, the preformatted man~pages arent necessary any longer.
The algorithm for retrieving man~pages uses five search methods. They are successively tried until a method works.
|The search path can be manually specified by using the option An empty argument disables the man~page searching. This overwrites the other methods.|
|If this is not available the environment variable is searched.|
|If this is empty, the program tries to read it from the environment variable|
|If this does not work a reasonable default path from is searched for man~pages.|
|If this does not work, the manpath(1) program for determining a path of man directories is tried.|
The locale (language) is determined like in GNU man, that is from highest to lowest precedence:
but the two-letter code in <language> is sufficient for most purposes.
If no man~pages for a complicated locale are found the country part consisting of the first two characters (without the CB]_], CB].], and CB],], parts) of the locale is searched as well.
If still not found the corresponding man~page in the default language is used instead. As usual, this default can be specified by one of CR]C] or CR]POSIX]. The man~pages in the default language are usually in English.
Several operating systems can be given by appending their names,
separated by a comma.
This is then specified by the environment variable
or by the command line option
The precedence is similar to the locale case above from highest to
The search can further be restricted by limiting it to certain sections. A single section can be specified within each filespec argument, several sections as a colon-separated list in command line option or environment variable When no section was specified a set of standard sections is searched until a suitable man~page was found.
Finally, the search can be restricted to a so-called extension. This is a postfix that acts like a subsection. It can be specified by or environment variable
For further details on man~page searching, see man(1).
DECOMPRESSIONThe 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.
ENVIRONMENTThe groffer programs 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
|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 white-space or special shell characters should be quoted.|
System VariablesThe groffer program is a shell script that is run through /bin/sh, which can be internally linked to programs like bash(1). The corresponding system environment is automatically effective. The following variables have a special meaning for groffer.
|If this variable is set this indicates that the X Window system is|
Testing this variable decides on whether graphical or text output is
This variable should not be changed by the user carelessly, but it can
be used to start the graphical groffer on a remote X terminal.
For example, depending on your system, groffer can be started on the
second monitor by the command
|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.|
|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
|All programs within the groffer shell script are called without a||fixed path. Thus this environment variable determines the set of programs used within the run of groffer.|
|If set to a non-empty value this chooses the POSIX mode.|
|This is done internally by some shells. groffer ignores the bad POSIX behavior for option processing, that means that option processing will be finished as soon as a non-option argument is found. Instead the GNU behavior of freely mixing options and filespec arguments is used in any case. Usually, you do not want to set this environment variable externally.|
Groff VariablesThe groffer program internally calls groff, so all environment variables documented in groff(1) are internally used within groffer as well. The following variables have a direct meaning for the groffer program.
|If the value of this variable is an existing, writable directory,|
|groffer uses it for storing its temporary files, just as groff does.|
Man VariablesParts 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 which in turn is overwritten by the command line.
|Restrict the search for man~pages to files having this extension.|
|This is overridden by option see there for details.|
|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 taht are specific to man. All options specified in this variable are overridden by the options given on the command line.|
|If set, this variable contains the directories in which the man~page|
|trees are stored. This is overridden by option|
|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|
|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 see there for details.|
CONFIGURATION FILESThe groffer program can be preconfigured by two configuration files. This configuration can be overridden at each program start by command line options or by the environment variable
|System-wide configuration file for groffer.|
|User-specific configuration file for groffer, where|
|denotes the users home directory. This script is called after the system-wide configuration file to enable overriding by the user.|
After the transformation of the minus lines the emerging shell scripts that are called by groffer using the filename syntax.
The only option that needs a minus line in the configuration files is The reason is that its argument must be called at a very early stage before the whole syntax of the configuration can be transformed.
It makes sense to use these configuration files for the following tasks:
|Preset command line options by writing them into lines starting with a minus sign.|
|Preset environment variables recognized by groffer.|
|Write a function for calling a viewer program for a special mode and feed this name into its corresponding option. Note that the name of such a function must coincide with some existing program in the system path in order to be recognized by groffer.|
# groffer configuration file
# groffer options that are used in each call of groffer
--x-viewer=gxditview -geometry 850x800
# some shell commands
if test "$DISPLAY" = ""; then
This configuration sets four groffer options and runs two shell commands. This has the following effects:
|Lines starting with a # character are|
|Use /bin/bash as the shell to run the groffer script.|
|Take a resolution of 100 dpi and a text color of DarkBlue in all viewers that support this.|
|Force gxditview(1) as the X-mode viewer using the geometry option for setting the width to 850 dpi and the height to 800 dpi.|
|The variable is set to localhost:0.0 which allows to start groffer in the standard X display, even when the program is called from a text console.|
|Just for fun, the date of each groffer start is written to the file mygroffer.log in the home directory.|
EXAMPLESThe 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.
COMPATIBILITYThe groffer shell script is compatible with both GNU and POSIX. POSIX compatibility refers to IEEE P1003.2/D11.2 of September 1991, a very early version of the POSIX standard that is still freely available in the internet. Unfortunately, this version of the standard has local for shell function variables removed. As local is needed for serious programming this temporary POSIX deprecation was ignored.
Most GNU shells are compatible with this interpretation of POSIX, but provide much more facilities. Nevertheless this script uses only a restricted set of shell language elements and shell builtins. The groffer script should work on most actual free and commercial operating systems.
The groffer program provides its own parser for command line options; it can handle option arguments and file names containing white space and a large set of special characters.
The groffer shell script was tested with the following common implementations of the GNU shells: POSIX sh(1), bash(1), and others. Free POSIX compatible shells and shell utilities for most operating systems are available at the
The shell can be chosen by the option This option can also be given to the environment variable If you want to write it to one of the groffer configuration files you must use the single option style, a line starting with
The groffer program provides its own parser for command line arguments that is compatible to both POSIX getopts(1) and GNU getopt(1) except for shortcuts of long options. The following standard types of options are supported.
|A single minus always refers to single character option or a combination thereof, for example, the groffer short option combination is equivalent to|
|Long options are options with names longer than one character; they are always prededed 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, is equivalent to|
|An argument of ends option parsing; all further command line arguments are interpreted as file name arguments.|
By default, 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
is, by default, equivalent to
is equivalent to
As this leads to unwanted behavior in most cases, most people do not want to set
|Details on the options and environment variables available in groff; all of them can be used with groffer.|
|man(1)||The standard program to diplay 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.|
|Viewers for groffers x mode.|
|Viewers for groffers ps mode.|
|gs(1)||Transformer from ps to pdf; and a ps viewer.|
|Viewers for pdf files.|
|Viewers for groffers dvi mode.|
|Standard pager program for the tty mode.|
|The decompression programs supported by groffer.|
|Documentation of the groff language.|
|Internally, groffer tries to guess the groff command line options from the input using this program.|
|Documentation on the groff intermediate output (ditroff output).|
AUTHORThis file was written by Bernd Warken.
COPYINGCopyright (C) 2001,2002,2004 Free Software Foundation, Inc.
This file is part of groff, a free software project. You can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.
You should have received a copy of the GNU General Public License along with groff, see the files COPYING and LICENSE in the top directory of the groff source package. Or read the man page gpl(1). You can also write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.