Ubuntu Manpage: groff_tmac - macro files in the roff typesetting system

NAME

       groff_tmac - macro files in the roff typesetting system

DESCRIPTION

       The  roff(7)  type-setting  system  provides  a set of macro packages suitable for special
       kinds of documents.  Each macro package stores its macros and definitions in a file called
       the package's tmac file.  The name is deduced from ‘TroffMACros’.

       The  tmac  files  are  normal roff source documents, except that they usually contain only
       definitions and setup commands, but no text.  All tmac files are kept in  a  single  or  a
       small number of directories, the tmac directories.

GROFF MACRO PACKAGES

groff provides all classical macro packages, some more full packages, and some secondary
packages for special purposes. Note that it is not possible to use multiple primary macro
packages at the same time; saying e.g.

sh# groff -m man -m ms foo

sh# groff -m man foo -m ms bar

fails. Exception to this is the use of man pages written with either the mdoc or the man
macro package. See below the description of the andoc.tmac file.

Man Pages
man This is the classical macro package for Unix manual pages (man pages); it is quite
handy and easy to use; see groff_man(7).

doc
mdoc An alternative macro package for man pages mainly used in BSD systems; it provides
many new features, but it is not the standard for man pages; see groff_mdoc(7).

andoc
mandoc Use this file in case you don't know whether the man macros or the mdoc package
should be used. Multiple man pages (in either format) can be handled.

Full Packages
The packages in this section provide a complete set of macros for writing documents of any
kind, up to whole books. They are similar in functionality; it is a matter of taste which
one to use.

me The classical me macro package; see groff_me(7).

mm The semi-classical mm macro package; see groff_mm(7).

mom The new mom macro package, only available in groff. As this is not based on other
packages, it can be freely designed. So it is expected to become quite a nice,
modern macro package. See groff_mom(7).

ms The classical ms macro package; see groff_ms(7).

Language-specific Packages
cs This file adds support for Czech localization, including the main macro packages
(me, mom, mm, and ms).

Note that cs.tmac sets the input encoding to latin-2.

de
den German localization support, including the main macro packages (me, mom, mm, and
ms).

de.tmac selects hyphenation patterns for traditional orthography, and den.tmac does
the same for the new orthography (‘Rechtschreibreform’). It should be used as the
last macro package on the command line.

fr This file adds support for French localization, including the main macro packages
(me, mom, mm, and ms). Example:

sh# groff -ms -mfr foo.ms > foo.ps

Note that fr.tmac sets the input encoding to latin-9 to get proper support of the
‘oe’ ligature.

sv Swedish localization support, including the me, mom, and ms macro packages. Note
that Swedish for the mm macros is handled separately; see groff_mmse(7) (only in
Swedish locales). It should be used as the last macro package on the command line.

Input Encodings
latin1
latin2
latin5
latin9 Various input encodings supported directly by groff. Normally, this macro is
loaded at the very beginning of a document or specified as the first macro argument
on the command line. roff loads latin1 by default at start-up. Note that these
macro packages don't work on EBCDIC hosts.

cp1047 Encoding support for EBCDIC. On those platforms it is loaded automatically at
start-up. Due to different character ranges used in roff it doesn't work on
architectures which are based on ASCII.

Note that it can happen that some input encoding characters are not available for a
particular output device. For example, saying

groff -Tlatin1 -mlatin9 ...

fails if you use the Euro character in the input. Usually, this limitation is present
only for devices which have a limited set of output glyphs (-Tascii, -Tlatin1); for other
devices it is usually sufficient to install proper fonts which contain the necessary
glyphs.

Special Packages
The macro packages in this section are not intended for stand-alone usage, but can be used
to add special functionality to any other macro package or to plain groff.

62bit Provides macros for addition, multiplication, and division of 62-bit integers
(allowing safe multiplication of 31-bit integers, for example).

ec Switch to the EC and TC font families. To be used with grodvi(1) – this man page
also gives more details of how to use it.

hdtbl The Heidelberger table macros, contributed by Joachim Walsdorff, allow the
generation of tables through a syntax similar to the HTML table model. Note that
hdtbl is a macro package, not a preprocessor like tbl(1). hdtbl works only with
the -Tps and -Tpdf output devices. See groff_hdtbl(7).

papersize
This macro file is already loaded at start-up by troff so it isn't necessary to
call it explicitly. It provides an interface to set the paper size on the command
line with the option -dpaper=size. Possible values for size are the same as the
predefined papersize values in the DESC file (only lowercase; see groff_font(5) for
more) except a7–d7. An appended l (ell) character denotes landscape orientation.
Examples: a4, c3l, letterl.

Most output drivers need additional command-line switches -p and -l to override the
default paper length and orientation as set in the driver-specific DESC file. For
example, use the following for PS output on A4 paper in landscape orientation:

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

pdfpic A single macro is provided in this file, PSPIC, to include a PDF graphic in a
document, i.e., under the output device -Tpdf. For all other devices, pspic is
used. So pdfpic is an extension of pspic. By that you can now even replace all
PSPIC by PDFPIC, nothing gets lost by that. The options of PDFPIC are identical to
the PSDIF options.

pic This file provides proper definitions for the macros PS and PE, needed for the
pic(1) preprocessor. They center each picture. Use it only if your macro package
doesn't provide proper definitions for those two macros (actually, most of them
already do).

pspic A single macro is provided in this file, PSPIC, to include a PostScript graphic in
a document. The following output devices support inclusion of PS images: -Tps,
-Tdvi, -Thtml, and -Txhtml; for all other devices the image is replaced with a
hollow rectangle of the same size. This macro file is already loaded at start-up
by troff so it isn't necessary to call it explicitly.

Syntax:

.PSPIC [-L|-R|-C|-I n] file [width [height]]

file is the name of the PostScript file; width and height give the desired width
and height of the image. If neither a width nor a height argument is specified,
the image's natural width (as given in the file's bounding box) or the current line
length is used as the width, whatever is smaller. The width and height arguments
may have scaling indicators attached; the default scaling indicator is i. This
macro scales the graphic uniformly in the x and y directions so that it is no more
than width wide and height high. Option -C centers the graphic horizontally, which
is the default. The -L and -R options cause the graphic to be left-aligned and
right-aligned, respectively. The -I option causes the graphic to be indented by n
(default scaling indicator is m).

For use of .PSPIC within a diversion it is recommended to extend it with the
following code, assuring that the diversion's width completely covers the image's
width.

.am PSPIC
. vpt 0
\h'(\\n[ps-offset]u + \\n[ps-deswid]u)'
. sp -1
. vpt 1
..

ptx A single macro is provided in this file, xx, for formatting permuted index entries
as produced by the GNU ptx(1) program. In case you need a different formatting,
copy the macro into your document and adapt it to your needs.

trace Use this for tracing macro calls. It is only useful for debugging. See
groff_trace(7).

tty-char
Overrides the definition of standard troff characters and some groff characters for
TTY devices. The optical appearance is intentionally inferior compared to that of
normal TTY formatting to allow processing with critical equipment.

www Additions of elements known from the HTML format, as used in the internet (World
Wide Web) pages; this includes URL links and mail addresses; see groff_www(7).

NAMING

       Classical roff systems were designed before the conventions of the modern C getopt(3) call
       evolved, and used a naming scheme for macro packages that looks odd to modern eyes.  Macro
       packages  were  always included with the option -m; when this option was directly followed
       by its argument without an intervening space, this looked like a long option preceded by a
       single  minus — a sensation in the computer stone age.  To make this invocation form work,
       classical troff macro packages used names that started with  the  letter  ‘m’,  which  was
       omitted in the naming of the macro file.

       For  example,  the  macro  package  for the man pages was called man, while its macro file
       tmac.an.  So it could be activated by the argument an to option -m, or -man for short.

       For similar reasons, macro packages that did not start with an ‘m’ had a leading ‘m’ added
       in the documentation and in speech; for example, the package corresponding to tmac.doc was
       called mdoc in the documentation, although a more suitable name would be doc.   For,  when
       omitting  the  space  between  the  option  and  its argument, the command-line option for
       activating this package reads -mdoc.

       To cope with all situations, actual versions of  groff(1)  are  smart  about  both  naming
       schemes  by providing two macro files for the inflicted macro packages; one with a leading
       ‘m’ the other one without it.  So in groff, the man macro package may be specified as  one
       of the following four methods:

              sh# groff -m man
              sh# groff -man
              sh# groff -mman
              sh# groff -m an

       Recent  packages  that  do  not  start  with  ‘m’  do  not  use  an  additional ‘m’ in the
       documentation.  For example, the www macro package may be specified only as one of the two
       methods:

              sh# groff -m www
              sh# groff -mwww

       Obviously, variants like -mmwww would not make much sense.

       A second strange feature of classical troff was to name macro files in the form tmac.name.
       In modern operating systems, the type of a file is specified as a postfix, the  file  name
       extension.   Again,  groff  copes  with this situation by searching both anything.tmac and
       tmac.anything if only anything is specified.

       The easiest way to find out which macro packages are available on a system is to check the
       man page groff(1), or the contents of the tmac directories.

       In  groff,  most  macro  packages  are described in man pages called groff_name(7), with a
       leading ‘m’ for the classical packages.

INCLUSION

       There are several ways to use a macro package in a document.   The  classical  way  is  to
       specify  the  troff/groff option -m name at run-time; this makes the contents of the macro
       package name available.  In groff, the file name.tmac is searched within the tmac path; if
       not found, tmac.name is searched for instead.

       Alternatively,  it  is  also  possible  to  include a macro file by adding the request .so
       filename into the document; the argument must be the full file name of an  existing  file,
       possibly  with the directory where it is kept.  In groff, this was improved by the similar
       request .mso package, which added searching in the tmac path, just like option -m does.

       Note that in order to resolve the .so and .mso requests, the roff  preprocessor  soelim(1)
       must  be  called  if the files to be included need preprocessing.  This can be done either
       directly by a pipeline on the command line or by using the  troff/groff  option  -s.   man
       calls soelim automatically.

       For example, suppose a macro file is stored as

              /usr/share/groff/1.22.4/tmac/macros.tmac

       and is used in some document called docu.roff.

       At run-time, the formatter call for this is

              sh# groff -m macros docu.roff

       To include the macro file directly in the document either

              .mso macros.tmac

       is used or

              .so /usr/share/groff/1.22.4/tmac/macros.tmac

       In both cases, the formatter should be called with option -s to invoke soelim.

              sh# groff -s docu.roff

       If  you  want  to  write  your own groff macro file, call it whatever.tmac and put it in a
       directory in the tmac path; see section “Files” below.  Then documents can include it with
       the .mso request or the option -m.

WRITING MACROS

A roff(7) document is a text file that is enriched by predefined formatting constructs,
such as requests, escape sequences, strings, numeric registers, and macros from a macro
package. These elements are described in roff(7).

To give a document a personal style, it is most useful to extend the existing elements by
defining some macros for repeating tasks; the best place for this is near the beginning of
the document or in a separate file.

Macros without arguments are just like strings. But the full power of macros reveals when
arguments are passed with a macro call. Within the macro definition, the arguments are
available as the escape sequences \$1, ..., \$9, \$[...], \$*, and \$@, the name under
which the macro was called is in \$0, and the number of arguments is in register \n[.$];
see groff(7).

Copy-in Mode
The phase when groff reads a macro is called copy-in mode or copy mode in roff-talk. This
is comparable to the C preprocessing phase during the development of a program written in
the C language.

In this phase, groff interprets all backslashes; that means that all escape sequences in
the macro body are interpreted and replaced by their value. For constant expressions,
this is wanted, but strings and registers that might change between calls of the macro
must be protected from being evaluated. This is most easily done by doubling the
backslash that introduces the escape sequence. This doubling is most important for the
positional parameters. For example, to print information on the arguments that were
passed to the macro to the terminal, define a macro named ‘.print_args’, say.

.ds midpart was called with
.de print_args
. tm \f[I]\\$0\f[] \*[midpart] \\n[.$] arguments:
. tm \\$*
..

When calling this macro by

.print_args arg1 arg2

the following text is printed to the terminal:

print_args was called with the following 2 arguments:
arg1 arg2

Let's analyze each backslash in the macro definition. As the positional parameters and
the number of arguments change with each call of the macro their leading backslash must be
doubled, which results in \\$* and \\[.$]. The same applies to the macro name because it
could be called with an alias name, so \\$0.

On the other hand, midpart is a constant string, it does not change, so no doubling for
\*[midpart]. The \f escape sequences are predefined groff elements for setting the font
within the text. Of course, this behavior does not change, so no doubling with \f[I] and
\f[].

Draft Mode
Writing groff macros is easy when the escaping mechanism is temporarily disabled. In
groff, this is done by enclosing the macro definition(s) into a pair of .eo and .ec
requests. Then the body in the macro definition is just like a normal part of the
document — text enhanced by calls of requests, macros, strings, registers, etc. For
example, the code above can be written in a simpler way by

.eo
.ds midpart was called with
.de print_args
. tm \f[I]\$0\f[] \*[midpart] \n[.$] arguments:
. tm \$*
..
.ec

Unfortunately, draft mode cannot be used universally. Although it is good enough for
defining normal macros, draft mode fails with advanced applications, such as indirectly
defined strings, registers, etc. An optimal way is to define and test all macros in draft
mode and then do the backslash doubling as a final step; do not forget to remove the .eo
request.

Tips for Macro Definitions
• Start every line with a dot, for example, by using the groff request .nop for text
lines, or write your own macro that handles also text lines with a leading dot.

.de Text
. if (\\n[.$] == 0) \
. return
. nop \)\\$*\)
..

• Write a comment macro that works both for copy-in and draft mode; for as escaping
is off in draft mode, trouble might occur when normal comments are used. For
example, the following macro just ignores its arguments, so it acts like a comment
line:

.de c
..
.c This is like a comment line.

• In long macro definitions, make ample use of comment lines or almost-empty lines
(this is, lines which have a leading dot and nothing else) for a better
structuring.

• To increase readability, use groff's indentation facility for requests and macro
calls (arbitrary whitespace after the leading dot).

Diversions
Diversions can be used to implement quite advanced programming constructs. They are
comparable to pointers to large data structures in the C programming language, but their
usage is quite different.

In their simplest form, diversions are multi-line strings, but they get their power when
diversions are used dynamically within macros. The (formatted) information stored in a
diversion can be retrieved by calling the diversion just like a macro.

Most of the problems arising with diversions can be avoided if you remain aware of the
fact that diversions always store complete lines. If diversions are used when the line
buffer has not been flushed, strange results are produced; not knowing this, many people
get desperate about diversions. To ensure that a diversion works, line breaks should be
added at the right places. To be on the secure side, enclose everything that has to do
with diversions into a pair of line breaks; for example, by explicitly using .br requests.
This rule should be applied to diversion definition, both inside and outside, and to all
calls of diversions. This is a bit of overkill, but it works nicely.

[If you really need diversions which should ignore the current partial line, use
environments to save the current partial line and/or use the .box request.]

The most powerful feature using diversions is to start a diversion within a macro
definition and end it within another macro. Then everything between each call of this
macro pair is stored within the diversion and can be manipulated from within the macros.

FILES

       All macro package files  must  be  named  name.tmac  to  fully  use  the  tmac  mechanism.
       tmac.name as with classical packages is possible as well, but deprecated.

       The  macro  files  are  kept  in  the  tmac  directories;  a colon separated list of these
       constitutes the tmac path.

       The search sequence for macro files is (in that order):

       •      the directories specified with troff/groff's -M command-line option

       •      the directories given in the GROFF_TMAC_PATH environment variable

       •      the current directory (only if in unsafe mode, which is enabled by the -U  command-
              line switch)

       •      the home directory

       •      a platform-specific directory, being

                     /usr/lib/groff/site-tmac

              in this installation

       •      a site-specific (platform-independent) directory, being

                     /usr/share/groff/site-tmac

              in this installation

       •      the main tmac directory, being

                     /usr/share/groff/1.22.4/tmac

              in this installation

ENVIRONMENT

       GROFF_TMAC_PATH
              A  colon separated list of additional tmac directories in which to search for macro
              files.  See the previous section for a detailed description.

AUTHORS

       This document was  written  by  Bernd  Warken  ⟨groff-bernd.warken-72@web.de⟩  and  Werner
       Lemberg ⟨wl@gnu.org⟩.