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Name | Synopsis | Description | Option Overview | Option Details | Output Modes | Man Page Searching | Decompression | Environment | Configuration Files | Example | Compatibility | Authors | See Also | COLOPHON |
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groffer(1) General Commands Manual groffer(1)
groffer - display groff files and man pages on X and tty
groffer [mode-option ...] [groff-option ...] [man-option ...] [X-
option ...] [--] [filespec ...]
groffer -h
groffer --help
groffer -v
groffer --version
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.
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.
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.
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.
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
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.
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.
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.
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.
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.
groffer was written by Bernd Warken ⟨groff-bernd.warken-72@
web.de⟩.
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.
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 2021-08-27. (At
that time, the date of the most recent commit that was found in
the repository was 2021-08-23.) 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)
Pages that refer to this page: roff2dvi(1), roff2html(1), roff2pdf(1), roff2ps(1), roff2text(1), roff2x(1)
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HTML rendering created 2021-08-27 by Michael Kerrisk, author of The Linux Programming Interface, maintainer of the Linux man-pages project. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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