groff_www(7) Miscellaneous Information Manual groff_www(7)
Name
groff_www - GNU roff macros for authoring web pages
Synopsis
groff -m www [option ...] [file ...]
Description
This manual page describes the GNU www macro package, which is part of
the groff(7) document formatting system. This macro file is
automatically loaded by the default troffrc file when the formatter
(usually groff(1)) is called with either of the options -Thtml or
-Txhtml. To see hyperlinks in action, format this man page using one
of those options.
This document is a basic guide; the HTML output driver (grohtml)
remains in an alpha state. It has been included with the distribution
to encourage testing.
Here is a summary of the functions found in this macro set.
.JOBNAME split output into multiple files
.HX automatic heading level cut off
.BCL specify colours on a web page
.BGIMG specify background image
.URL create a URL using two parameters
.FTP create an FTP reference
.MTO create an HTML email address
.TAG generate an HTML name
.IMG include an image file
.PIMG include PNG image
.MPIMG place PNG on the margin and wrap text around it
.HnS begin heading
.HnE end heading
.LK emit automatically collected links.
.HR produce a horizontal rule
.NHR suppress automatic generation of rules.
.HTL only generate HTML title
.HEAD add data to <head> block
.ULS unorder list begin
.ULE unorder list end
.OLS ordered list begin
.OLE ordered list end
.DLS definition list begin
.DLE definition list end
.LI insert a list item
.DC generate a drop capital
.HTML pass an HTML raw request to the device driver
.CDS code example begin
.CDE code example end
.ALN place links on left of main text.
.LNS start a new two-column table with links in the left.
.LNE end the two-column table.
.LINKSTYLE initialize default URL attributes.
Macros
.JOBNAME filename
Split output into multiple HTML files. A file is split whenever
a .SH or .NH 1 is encountered. Its argument is the file stem
name for future output files. This option is equivalent to
grohtml's -j option.
.HX n Specify the cut off depth when generating links from section
headings. For example, a parameter of 2 would cause grohtml to
generate a list of links for .NH 1 and .NH 2 but not for .NH 3.
Whereas
.HX 0
tells grohtml that no heading links should be created at all.
Another method for turning automatic headings off is by issuing
the command-line switch -P-l to groff.
.BCL foreground background active not-visited visited
This macro takes five parameters: foreground, background, active
hypertext link, hypertext link not yet visited, and visited
hypertext link colour.
.BGIMG imagefile
the only parameter to this macro is the background image file.
.URL url [description] [after]
generates a URL using either one, two, or three arguments. The
first parameter is the actual URL, the second is the name of the
link, and the third is optional stuff to be printed immediately
afterwards. If description and after are absent then the URL
becomes the anchor text. Hyphenation is disabled while printing
the actual URL; explicit breakpoints should be inserted with the
\: escape sequence. Here is how to encode foo <http://foo
.org/>:
.URL http://\:foo\:.org/ foo :
If this is processed by a device other than -Thtml or -Txhtml it
appears as:
foo <http://foo.org>:
The URL macro can be of any type; for example, we can reference
Eric Raymond's pic guide <pic.html> by:
.URL pic\:.html "Eric Raymond's pic guide"
.MTO address [description] [after]
Generate an email HTML reference. The first argument is
mandatory as the email address. The optional second argument is
the text you see in your browser. If an empty argument is
given, address is used instead. An optional third argument is
stuff printed immediately afterwards. Hyphenation is disabled
while printing the actual email address. For example, Joe User
<joe@user.org> can be achieved by the following macro:
.MTO joe@user.org "Joe User"
All URLs currently are treated as consuming no textual space in
groff. This could be considered as a bug since it causes some
problems. To circumvent this, www.tmac inserts a zero-width
character which expands to a harmless space (only if run with
-Thtml or -Txhtml).
.FTP url [description] [after]
indicates that data can be obtained via FTP. The first argument
is the URL and the second is the browser text. A third
argument, similar to the macros above, is intended for stuff
printed immediately afterwards. The second and the third
parameter are optional. Hyphenation is disabled while printing
the actual URL. As an example, here is the location of the GNU
FTP server <ftp://ftp.gnu.org/>. The macro example above can be
specified as:
.FTP ftp://\:ftp\:.gnu\:.org/ "GNU FTP server" .
.TAG name
Generates an HTML name tag from its argument. This can then be
referenced using the URL <#URL> macro. As you can see, you must
precede the tag name with # since it is a local reference. This
link was achieved via placing a TAG in the URL description
above; the source looks like this:
.TP
.B URL
generates
.TAG URL
a URL using either two or three arguments.
...
.IMG [-R|-L|-C] filename [width] [height]
Include a picture into the document. The first argument is the
horizontal location: right, left, or center (-R, -L, or -C).
Alignment is centered by default (-C). The second argument is
the filename. The optional third and fourth arguments are the
width and height. If the width is absent it defaults to 1 inch.
If the height is absent it defaults to the width. This maps
onto an HTML img tag. If you are including a PNG image then it
is advisable to use the PIMG macro.
.PIMG [-R|-L|-C] filename [width [height]]
Include an image in PNG format. This macro takes exactly the
same parameters as the IMG macro; it has the advantage of
working with PostScript and HTML devices also since it can
automatically convert the image into the EPS format, using the
following programs of the netpbm package: pngtopnm, pnmcrop, and
pnmtops. If the document isn't processed with -Thtml or -Txhtml
it is necessary to use the -U option of groff.
.MPIMG [-R|-L] [-G gap] filename [width [height]]
Place a PNG image on the margin and wrap text around it. The
first parameters are optional. The alignment: left or right (-L
or -R) specifies the margin where the picture is placed at. The
default alignment is left (-L). Optionally, -G gap can be used
to arrange a gap between the picture and the text that wraps
around it. The default gap width is zero.
The first non-optional argument is the filename. The optional
following arguments are the width and height. If the width is
absent it defaults to 1 inch. If the height is absent it
defaults to the width. Example:
.MPIMG -L -G 2c foo.png 3c 1.5c
The height and width may also be given as percentages. The
PostScript device calculates the width from the .l register and
the height from the .p register. For example:
.MPIMG -L -G 2c foo.png 15%
.HnS n Begin heading. The numeric heading level n is specified by the
first parameter. Use this macro if your headings contain URL,
FTP or MTO macros. Example:
.HnS 1
.HR
GNU Troff
.URL https://\:www\:.gnu\:.org/\:software/\:groff/
\[em]a
.URL http://www\:.gnu\:.org/ GNU
project.
.HR
.HnE
In this case you might wish to disable automatic links to
headings. This can be done via -P-l from the command line.
.HnE End heading.
.LK Force grohtml to place the automatically generated links at this
position.
.HR Generate a full-width horizontal rule for -Thtml and -Txhtml.
No effect for all other devices.
.NHR Suppress generation of the top and bottom rules which grohtml
emits by default.
.HTL Generate an HTML title only. This differs from the TL macro of
the ms macro package which generates both an HTML title and an
<H1> heading. Use it to provide an HTML title as search engine
fodder but a graphic title in the document. The macro
terminates when a space or break is seen (.sp, .br).
.HEAD Add arbitrary HTML data to the <head> block. Ignored if not
processed with -Thtml or -Txhtml. Example:
.HEAD "<link \
rel=""icon"" \
type=""image/png"" \
href=""http://foo.org//bar.png""/>"
.HTML All text after this macro is treated as raw HTML. If the
document is processed without -Thtml or -Txhtml then the macro
is ignored. Internally, this macro is used as a building block
for other higher-level macros.
For example, the BGIMG macro is defined as
.de BGIMG
. HTML <body background=\\$1>
..
.DC l text [color]
Produce a drop capital. The first parameter is the letter to be
dropped and enlarged, the second parameter text is the adjoining
text whose height the first letter should not exceed. The
optional third parameter is the color of the dropped letter. It
defaults to black.
.CDS Start displaying a code section in constant width font.
.CDE End code display
.ALN [color] [percentage]
Place section heading links automatically to the left of the
main text. The color argument is optional and if present
indicates which HTML background color is to be used under the
links. The optional percentage indicates the amount of width to
devote to displaying the links. The default values are #eeeeee
and 30 for color and percentage width, respectively. This macro
should only be called once at the beginning of the document.
After calling this macro each section heading emits an HTML
table consisting of the links in the left and the section text
on the right.
.LNS Start a new two-column table with links in the left column.
This can be called if the document has text before the first .SH
and if .ALN is used. Typically this is called just before the
first paragraph and after the main title as it indicates that
text after this point should be positioned to the right of the
left-hand navigational links.
.LNE End a two-column table. This should be called at the end of the
document if .ALN was used.
.LINKSTYLE color [ fontstyle [ openglyph closeglyph ] ]
Initialize default URL attributes to be used if this macro set
is not used with the HTML device. The macro set initializes
itself with the following call
.LINKSTYLE blue CR \[la] \[ra]
but these values will be superseded by a user call to LINKSTYLE.
Section heading links
By default grohtml generates links to all section headings and places
these at the top of the HTML document. (See LINKS <#LK> for details of
how to switch this off or alter the position).
Limitations of grohtml
tbl(1) tables are rendered as PNG images. Paul DuBois's approach with
tblcvt(1), part of the troffcvt distribution <http://www.snake.net/
software/troffcvt/>, should be explored.
Files
/opt/local/share/groff/1.23.0/tmac/www.tmac
Authors
The www macro package was written by Gaius Mulley <gaius@glam.ac.uk>,
with additions by Werner Lemberg <wl@gnu.org> and Bernd Warken
<groff-bernd.warken-72@web.de>.
See also
groff(1), troff(1), grohtml(1), netpbm(1)
groff 1.23.0 2 July 2023 groff_www(7)
groff 1.23.0 - Generated Fri Dec 22 19:38:47 CST 2023